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24a Locke, Essay III.iii.1-4,6-13,15-18 Abstract Ideas At Essay
II.xxi.5, Locke remarked that Perception,
which we make the act of the Understanding, is of three sorts: 1. The
Perception of Ideas in our Minds. 2.
The Perception of the signification of Signs. 3. The Perception of the
Connexion or Repugnancy, Agreement or Disagreement, that there is between any
of our Ideas. All these are attributed to the Understanding, or perceptive Power,
though it be the two latter only that use allows us to say we understand. Locke’s survey of our various simple
and complex ideas over Book II of the Essay
was an examination of the first of these three sorts of perception. In Book III, he turned to consider the
second sort, the perception of ideas upon the occasion of hearing or reading
names or other signs that we have come to associate with those ideas, and he
considered some of the philosophical issues that arise in connection with the
use of words and language in general.
Essay III.iii and III.vi are devoted to two particularly important
issues that arise in connection with naming, the problem of universals and
the problem of natural kinds. In
order to appreciate what Locke was up to in these two chapters, it helps to recall
some of the views that have traditionally been taken on these two topics. The problem of universals is the
problem of what our general terms refer to.
Since at least the time of Plato, philosophers have wondered whether
general terms name general objects, or whether everything that exists is a
particular. For example, they have
wondered whether, in addition to all the different human beings who have ever
existed, there is also such a thing as humanity, which exists distinct from
any one human being. Plato famously
propounded the latter view, holding that our general terms do not refer to
collections of individuals, but to “forms.”
He held that these forms are more real than particular individuals and
that individuals only get their particular characters
through “participating” in them. He
also supposed that these forms can only be known by the soul or the
intellect, and that the particular objects in the sensible world are merely
pale imitations, that at best lead our minds to recollect their past experience
of these forms. Aristotle also held that there are
general things. But he held that these
things do not exist separately from particular individuals. The substantial form of human being, for example,
is the general form of humanity existing in each human being. Aristotle’s position gives rise to a
“problem of the one and the many,” classically articulated by Boethius in his
commentary on Porphyry’s “Isagoge” — itself a
commentary on Aristotle’s “De Interpretatione.” How can the universal be one thing if it
exists in many different instances? Other philosophers, troubled, in part,
by the untenability of Plato’s theory and the
one/many problem associated with Aristotle’s, held that it is just too
implausible to suppose that there are general things. But taking this
position meant that these philosophers had to come up with some account of
what our general words refer to. Some,
collectively referred to as the conceptualists, held that while there are no
general things, the mind is able to form general ideas or concepts, and that
our general terms name these concepts.
(Locke is in this group.)
Others, the nominalists, held that the only things that are general
are names, and that even they are made general only by being used to refer to
collections of particulars that have been observed to resemble one another in
some way. (Hobbes is in this group.) The problem of natural kinds deals with a closely related issue: it asks about
the basis for collecting individuals together in one way rather than another. There have been two main positions taken in
answer to this question. One position
is essentialism. It is the view that there is something, variously called an
essence or general nature or substantial form, that is found in certain
things and not others, and that makes these things all exhibit common
features, behave in a characteristic way, and grow or evolve in the same way
over time. It is important to get the
direction right here: According to
essentialist, it is because certain
things all have the same essence that they resemble one another, so the
essence comes first and because it is present in certain things and not in
others it forces them to be alike in various ways. In the case of things capable of
reproduction, this essence gets transmitted from the parent to the offspring,
ensuring that the offspring will be of the same kind as the parent. Kinds, on the essentialist view, are
properly based on these essences, natures, or forms,
and classification schemes are right or wrong depending on whether they
conform to them. In things capable of
reproduction, kinds are indicated by reproductive abilities. For example, the fact that a Labrador
retriever and a great Dane can mate and bear fertile offspring is taken to
indicate that they share the same essence and so belong to the same species,
whereas the fact that a horse and a donkey cannot produce fertile offspring
is taken to indicate that there is no common essence and that the two
therefore belong to different species. By way of further example, consider
the following classification schemes:
An essentialist would probably hold that
at least some of these classification schemes do not capture “natural kinds,”
that is, that they do not group things in a way that reflects the essences or
forms in them that give them the qualities that they are observed to have. An apple and a stoplight, the essentialist
would claim, likely do not have any nature or essence in common. At best, they have different essences
(supposing for the sake of illustration that artifacts like stoplights can
properly be taken to have essences) that accidentally happen to cause them to
exhibit some common features. The last item on the table,
incidentally, is an indication that the problem of natural kinds is no mere
metaphysical technicality but is rather an issue that, at least where some
kinds are concerned, can be taken to have sociopolitical and ethical
implications. If there are true
natural kinds, then things that fail to conform to them can be called
deformed and monstrous, with all the implications that those terms
carry. (Or, some things that do conform
to them can be declared to be merely one sub-species, not fully
representative of the genus as a whole.) In contrast to essentialism,
conventionalism claims that there are no common essences that make certain
things all exhibit resembling features.
Everything is similar to everything else in some way or other, and the
particular similarities we happen to pick on are governed by our own
interests and customs and do not reflect any essence or nature in things — at
any rate none that we can know of. For the conventionalist, therefore,
there are no “natural kinds” and all of the classification schemes listed on
the table above are equally arbitrary. Over Essay III.iii and vi Locke took a
conceptualist line on the problem of universals and a conventionalist line on
the problem of natural kinds. The only
things that exist are particulars, Locke insisted. There are no Platonic Forms, and no
universal things. There are also no
essences in things. Or, at least,
there are no essences of the sort Aristotle had supposed. That is, there are no natures or
substantial forms that are present in certain things and not in others and
make those things belong to certain kinds or sorts. Of course, there is something in each
individual thing that makes that thing what it is and that makes it cause the
collection of ideas in us that it does, namely, the arrangement of solid,
shaped and moving parts that accounts for its macroscopic primary qualities,
and its secondary and tertiary qualities. But these arrangements of shaped and
moving parts are unique to each thing, not shared in common by many. The only things that could even possibly
have identical arrangements of identically shaped, solid and moving parts are
perfectly identical twins, and even
in such things, were they to exist, there might be some small variations, if
only arising from their being differently located in space and as a
consequence interacting in different ways with their environments. This is not something we tend to think
today. Today we think that, at least
at the level of materials, there are common forms and essences. We think that
substances like water are commonly characterized by having two atoms of
hydrogen and one of oxygen, and that elements like
oxygen and hydrogen are characterized by their atomic structures. Locke simply did not share this view. Even were he alive today, he would probably
have charged that our definitions of water, hydrogen, and oxygen are merely
“nominal.” Exactly what this means
will be explained in a moment, but for now take it to mean that he would have
said that these definitions are idealizations that only capture a part of
what any actual sample of these materials is like. To back his point up, he would have
appealed to impurities and things like isotopes to argue that no two samples
are ever exactly the same, and that even any given atom of oxygen is going to
differ in some way from any other, often in ways (as with isotopes) that
chafe at the hard boundaries we imagine to exist between the elements. Just as our definitions of water, oxygen,
and hydrogen only capture a part of what any given sample of these materials
is like, so they capture only a part of what makes any given sample what it
is, and the part that they capture is ultimately only an arbitrarily selected
part, not something that offers a more natural or appropriate or just
definition of the true or real essences of particular things. Locke thought that the contrary belief
in the existence of universal things and shared substantial forms or essences
has arisen because of an uncritical attitude to the meaning of names. Though there are no general or universal
things, we have, for a number of good reasons, come to use particular words
to stand for whole groups of things.
Thus, there are general words or terms. People have wrongly supposed that because
there are general words or terms, there must be general things that these
terms name, and then they have made the further error of supposing that these
general things are essences or natures that make the things that possess them
be a certain way. As it turns out, our general terms
only name certain general or universal ideas in the mind. These ideas are formed by abstraction. When
we abstract we take an idea and separate it from the other ideas that
typically surround and accompany it when it is actually perceived,
particularly from any ideas that might serve to attribute it to a particular
time and place. (As we have already
learned, location in time and space individuates and so particularizes things
for Locke.) This abstraction can be of one or the
other of two kinds. In one kind of
abstraction we consider just one simple idea apart from all others. For example, upon perceiving a sugar cube I
might separate the idea of sweetness from all the other ideas that accompany
it in the perception and just consider that one simple idea on its own. This sort of abstraction yields what might
be called an attributive universal. It
is a straightforward operation and Locke was not particularly concerned with
it. Another kind of abstraction occurs
when I perceive a substance and I abstract a collection of different simple
ideas from it. For example, upon perceiving a human being or another animal I
might abstract the ideas of extension, a certain arrangement of organic
parts, and a power of sensation and motion.
Unlike the first kind of abstraction, which generates one simple idea,
this second kind of abstraction generates a list of simple ideas (though by
no means a complete list of all the simple ideas that occur in the perception
of any particular object). This list
serves as a formula for identifying a sort or kind of substance (in this
case, an animal). It is not a
straightforward operation, since we need to wonder whether there is any good
reason why this particular, small collection of ideas should have been
abstracted from the infinitely rich collection of ideas we can get by
attending in different ways to the sensations any given object brings about
in us. Locke referred to the idea that
arises from this second kind of abstraction as a “sortal.” It is these sortal
ideas, and not universals or essences, that our
general terms name. QUESTIONS
ON THE
1. What does the
meaning of words depend on? (Note: the answer to this question is only to be
found in the complete edition of the text, not in Winkler’s abridgment,
though it can still be gleaned from passages included here and there in
Winkler. For for
electronic copy of the complete text see the instructions.)
2. What is the
purpose of language?
3. How do words
come to have a general meaning? (Keep
your answer to #1 in mind when dealing with this question.)
4. How do ideas
come to be general?
5. Why is it
particularly important that relations of time and place be removed when ideas
are made general?
6. What do
general words signify, according to Essay III.iii.12? Why do they not signify a number of things?
7. What is the
real essence of an individual substance?
8. What is the
nominal essence of a genus, sort, or kind of substance?
9. Are there any
things whose real essences may be known by us? NOTES
ON THE When we start off naming substances we
naturally give each particular we encounter its own name. But it is not feasible to continue doing
this forever. Rather than give names
to each particular object we encounter, we come up with names that refer to
whole groups of objects. In fact, most of the names we use are names of
groups of things, not of individual objects.
“Table,” “tree,” “pen,” “window” are just some examples. There are surprisingly few things that have
their own special names: human beings do, but not animals (just our pets),
and in addition to these almost the only individuals that have their own
names are the things we map: cities and their streets, geographical and
cosmological features and events in human history. There are a number of good reasons for
this widespread use of general terms. For one thing, if we had to give every
dust ball and house fly we came across a different name, we would never be
able to remember them all. But even if we could keep distinct
ideas of each different thing in our memories, giving everything its own name
would make it almost impossible for us to communicate with one another,
because no one would understand the names used for particular objects they
had not personally experienced. Finally, even if we could feasibly
communicate with one another without using general terms, such extreme
particularization in our discourse would impose severe restrictions on our
knowledge. It would be impossible to
formulate general rules like the rule that you can get rabies from a dog
bite, but not AIDS, or that rats carry bubonic plague, but not yellow
fever. Even supposing anyone could
notice these general correlations without using general names, it would be
impossible to convey that knowledge to anyone else. But if all things that exist are
particular, what are we talking about when we use general terms? There would seem to be three
possibilities. We could suppose that
our general terms are names of essences that are contained in certain things
and not in others and that make those things be what
they are. (This seems to be the view
underlying the attempt to formulate scientific laws such as the law that
bubonic plague is transmitted by rats.
If it is just these things and not others that have this effect, then
there must be something about them —something characteristic of them that
makes them what they are and that only they share — in virtue of which they
do this.) Alternatively, we could
suppose that our general terms are names for certain collections of simple
ideas that we have observed to be common to a number of substances and
abstracted from the particular circumstances of their original perception. Finally we could suppose that they are
names for the individual substances themselves — names that are applied to
certain substances in common because, for whatever reason, we have grouped
them together. (The difference between
the second and the third alternatives is that, according to the second
alternative, our name refers to a single abstract idea of the respects in
which the members of a group resemble one another, whereas on the third
alternative our name just refers to the members in the group.) Locke rejected the first of these
alternatives for two different reasons — each reason being directed against a
particular view of what the essence of a thing might be. One of these views is the view “taught in
the schools” as Locke put it. This is
the view of Plato and Aristotle, that essences are “substantial forms.” Locke’s reasons for rejecting this view
were blunt. He declared it to be
unintelligible and therefore a mere use of words to paper over our ignorance
of what we are talking about when we claim that there are essences in
things. The second view is one that he
considered to be far more intelligible, though ultimately just as false (for
reasons to be considered when we turn to the next section). This is the view that the essence of things
arises from how their component parts are arranged and moving. At this point, Locke did not give his
reasons for rejecting the view that there are any such “real essences.” He merely appealed to what he had said over
Essay II.viii.7-26 and II.xxiii to establish that even if there were any such
real essences, we could not know them.
Any real essences in things would have to be understood to be either
something to do with the primary qualities of their insensibly small parts,
which give them the power to have the effects they do on us and other things,
or something to do with the substance or substratum in which these primary
qualities inhere.
But we do not have microscopical eyes and so
cannot see the corpuscular constitution of things, and we have only a
relative idea of the supposed substance or substratum. In other words, we have no adequate idea of
either of these things. We only have
ideas of their effects: the collections of simple ideas they bring about in
us. Given this rejection of the first
alternative, there are still two ways Locke could go to describe how general
terms are related to ideas. He could say that our general terms refer to
certain general ideas that we have or he could say that there are no such
things as general ideas and that what makes a word general is just that we
use it to refer to each one of a whole collection of different objects. Neither of these alternatives is an
entirely happy one. If you take the
first alternative then you have to explain what a general idea is and how it
is possible to have one. Locke’s
British successors, Berkeley and Hume, thought it is impossible to have
general (or, as they called them, abstract) ideas, so they took the second
route. But in III.iii.12 Locke
rejected this position on the ground that it would mean that all of our
general terms would have to be collective rather than individual, that is,
that they would have to refer to all the members of the group rather than to
the group as a unit. Locke seems to
have thought that this is just patently wrong. Our general terms refer to one thing, he
claimed, not to many. “Cat” refers to
a sort of thing, not a bundle of things.
Otherwise, we would not use the singular term, “cat,” but the plural,
“cats.” We might well wonder about
this. The fact that “cat” is a singular
term hardly seems to decide the issue.
As anyone who has taken a course in basic predicate logic can attest,
the fact that we say, “The cat is a fearsome hunter,” does not prevent us
from translating the sentence using a universally quantified variable (one
that ranges over all the members of the domain that satisfy the predicate
“cat.” There are many features of
English usage that are merely idiomatic and that do not accurately reflect
the underlying meaning of the claim being made. There are better arguments Locke might
have used to justify his position.
Since some species can have very large numbers of members, there is no
way our general terms could name them, because we would never think of all of
them when using the term. We could at
best think of just a few and that might make our ideas over-determinate. If I think of just a few triangles (because
there are just too many to imagine them all) then I may infer all triangles
to necessarily have some features that just those I happen to be thinking of
possess and so will not get the concept right. If we largely avoid doing this, it may be
because we are in fact working with some idea or concept that defines the
group rather than just a collection of individuals. A further problem with nominalism is
that it begs the question of what leads us to certain things together under a
general name and exclude others from the collection. Would we not have to perceive something
that is shared in common between all the members of the group and that
qualifies some particulars for inclusion in the group while excluding
others? It seems we need to be able to
form an “abstract idea” of the targeted commonality and find it in any member
of the group. But then abstract ideas
are not just names. Having argued that our general terms
refer to abstract ideas, Locke went on to consider how these ideas might be
formed. He supposed that we start off
with an experience of particular substances, obtained from perception. Recall that our perceptions of particular
substances consist of a number of simple ideas, commonly observed to go
together. Though they go together, these simple ideas are all perfectly
distinct and distinguishable from one another by an attentive mind. Any one of them can therefore be easily
separated from all of the rest. This
is what we do when we form our abstract ideas of uniform qualities, like
black, white, red, and hot. This
operation, whereby many of our ideas of attributes of things is formed, is
unproblematic and Locke did not discuss it further. However, we also perform another kind of
abstraction where we do not just separate a single simple idea from all of
the rest, but a collection of simple ideas from all of the rest, forming an
abstract idea of a type or sort of substance.
This is the operation that Locke particularly wanted to
understand. What is it that determines
us to collect and abstract a certain group of simple ideas from out of the
entire collection we receive when we experience a particular substance,
rather than some other group? The short answer to this question is
that abstraction is guided by the perception of similarity or commonality
between different particulars. Having
once obtained experiences of a number of different, particular substances, we
compare them with one another. Each of
these substances is described by a distinct collection of simple ideas.
However, some of these collections of simple ideas “overlap,” so to
speak. They contain a number of simple
ideas in common. Once we notice that a number of
different substances resemble one another by all including certain simple
ideas among the other ideas in their bundles, we abstract or separate these
common simple ideas and represent them by themselves. As long as the abstraction leaves out any
reference to a specific time and place (which for Locke serve to individuate
things from one another, as Essay II.xxvii taught), the idea thus formed will not refer to
any one substance but will rather represent just what is common to the entire
group of substances that share those resembling characteristics. It will be, in effect, a general idea. Having formed this idea we proceed to give
it a name. The definition of this name is just the list of names for the
simple ideas that go into the abstract idea. Here is an example of what Locke had
in mind. We start off identifying
different, particular substances, say, our mothers, our aunts, our
nurses. We then notice that all of
these substances, however different they may be from one another in other
respects, all give us certain simple ideas.
We abstract the common simple ideas from the ones that vary from
substance to substance and form an idea just of the union of the common
simple ideas. We give this idea a
name: human. This name serves as a
general term that we can use to refer to all the substances that share those
same simple ideas. Sometimes, the simple ideas that we
abstract are ones that go together in the more complex ideas we form of
tertiary qualities, that is, powers in things to affect other things in
certain ways. The power to mate and
reproduce viable offspring is one example, and one that we allow to play a
significant role in our identification of animal species. Having formed general ideas for a
number of specific kinds of things, we also form yet more general ideas for
their genera. For example, we notice
that all the substances we call humans share something in common with all the
substances we call cats. We abstract
this more restrictive set of common simple ideas and give it the name,
animal. Then we notice that all
animals share something in common with all the substances we call
plants. We abstract this more
restrictive set of common simple ideas and give it the name, living thing. And so on for the formation of more and
more general concepts. As Essay III.iii.7 indicates, Locke
took this procedure to actually reflect our developmental psychology. He supposed that children first learn to
name particular objects and only gradually develop the ability to abstract
more and more general concepts. Insofar as they function to pick out
sorts of things, Locke called abstract ideas “sortals.” Other, equally good names for them are
“genus concepts,” or “generic concepts.”
You should not confuse sortals or generic
concepts with attributive universals.
In the tradition Locke was brought up in, people would refer to
properties, qualities and attributes like “red” or “sweet” or “triangular” or
“just” as universals. But for Locke,
these things are not sortals. They are simple ideas or simple or complex
modes. What makes an idea a sortal is that it refers to a group or sort of
substances, not to a single property, quality or attribute that some
substance or some number of substances may have. Sortals are like
complex modes, however, in that they are made up of a number of simple
ideas. But whereas complex modes are
created by combining a number of simple ideas together in such a way that
they make up some quality, property or attribute that is thought of as being
unable to exist on its own, sortals are created by
abstracting a number of simple ideas from a perception in such a way as to
still refer to some collection of substances, the members of which are each
able to exist on their own. Locke observed that authors of logic
textbooks have commonly held that the proper way to define sorts of thing is
to list the genus to which all the things of that sort belong, and then
mention the specific thing that differentiates that sort from the other sorts
or “species” of things that fall under the genus (the so-called “specific
difference”). One still finds this practice recommended in logic textbooks
written today. By way of illustration,
the sort, human being, would be defined by giving the genus, animal, and the
specific difference, rational. Locke objected to this practice because it
conveys the impression that in specifying the genus, animal, we are
identifying some form that all the different sorts of things that fall under
the genus share in common, and that in specifying the specific difference we
are identifying some kind of essence that makes all the things in the sort
exhibit the features characteristic of that particular sort or species. In fact, we are doing neither of these
things. The name for the genus is just
the name for a collection of simple ideas observed to be shared in common by
a group of substances, and we only use the name for the genus because we are
too lazy to list all of the names for these simple ideas individually (or,
worse, because we do not really understand the exact signification of the
general term and are merely covering up our ignorance). The name for the specific difference is
simply the name for a further, particularly important, simple idea or
collection of simple ideas. If we are
to avoid ambiguity in language and the temptation to suppose there are
universal things and essences, we ought to always define general terms by
listing the names for all the simple ideas they are intended to arouse in the
mind of the hearer, and should not talk about genera and specific
differences. Locke’s account of general terms has
some implications that should be remarked upon: (i) If Locke
is right, then our general terms do not name general or universal
things. They only name abstract
ideas. These abstract ideas are
collections of simple ideas observed to be common to our perceptions of a
number of different substances. As
such, they have some foundation in the nature of things. Different things have to resemble one
another in some way or other for us to be able to abstract ideas of the ways they
resemble one another. But abstract
ideas are also artifacts of our understanding to the extent that we decide
which of the infinitely many different sorts of resemblances between things
to notice. As a cursory consideration
suffices to show, everything resembles everything else in some way or other
(though the way in which thing A resembles thing B may be quite different
from the way in which thing A resembles thing C or thing C thing B). So abstracting ideas of certain
resemblances will cause certain things to be grouped together, while
abstracting other resemblances will cause those same things to be grouped
together in a different way. (For
instance, the animals in a farmyard may be grouped in one way by species, in
another by sex, in a third by maturation, and so on.) Any one thing can in principle be grouped
with any other thing, simply by abstracting an idea of the appropriate
resemblance, though then what other third, fourth, and further things get
included in this group is determined by the natures of things, that is, by
which other things also have the resembling feature, and is not something
that we can determine. But aside from
this one limitation, the organization and classification of things on the
basis of resembling ideas is something that we do. We pick what resemblances to abstract and
we pick what names to give to the abstract ideas thus formed. (ii) On Locke’s account, the
definition of a general term is just the list of simple ideas it refers
to. But it is quite possible that different
people might abstract different sets of resembling, simple ideas from the
same collection of individuals. Thus,
a child may look at various pieces of gold and abstract no more than the idea
of a yellow, uniformly coloured, hard, solid, smooth body, whereas a
metallurgist would understand gold to have a certain mass, and characteristic
mechanical and chemical properties, such as malleability and fusibility. The child’s definition will obviously
encompass a much larger collection of things than the metallurgist’s. For example, the child will consider brass
to be gold. We can expect this
situation to be replicated quite broadly.
The same general term can be expected to be defined differently by
different people and different cultures, or by people with different
occupations or interests. But as long
as people are explicit about exactly what simple ideas they mean to include
under or exclude from the meaning of a general term, there is no right or
wrong in the matter. For instance, one
person or one culture may understand the general term “human being” to
include the idea of independent viability, and so to exclude fetuses and
people on life-support. Another person
or culture may take certain intellectual abilities to be part of the
definition of a human being and so include whales, dolphins, and elephants,
or even certain computing devices under the definition of human being while
excluding very young children or people in a persistent vegetative
state. And no one could criticize
these definitions for being right or wrong.
Definitions could only be criticized for being vague or
ambiguous. (Of course, once people
have defined their terms a certain way, it is still a serious question what
rights and privileges might be due to the individuals collected together by
the terms. Thus, issues of abortion,
animal rights, and euthanasia are not to be decided by the meaning of
words. Even if “human being” is
broadly defined, it might still be a question whether all human beings
deserve the same rights, and even if “human being” is narrowly defined, it
might still be a question whether certain rights ought to be extended to
so-called non-human individuals. The
flip side of this coin, however, is that claims about the essential nature of
human beings cannot be used to decide these questions. For, if Locke is right, we have no
knowledge of any real essence. I
comment further on this in the next paragraph.) (iii) If we understand the term
“essence” to refer to something a substance has to have in order to be considered
a thing of a certain kind, so that were it to lose this thing, it would be
destroyed or transformed into a different kind of thing, then our abstract
ideas are the only “essences” we know.
But since our abstract ideas are produced by our understanding, it
follows that the essences of things, likewise, are not something internal to
the things themselves, but something we ourselves have created. It is only because we have decided to
notice certain resemblances and have abstracted ideas of them that the simple
ideas contained in those abstract ideas have been elevated to the status of
ideas of essences that things have to have.
As a matter of fact, everything
is essential to an individual thing considered just as an individual thing
(which is the same as to say that nothing is, or
that no change deserves to be considered to be more essential than any
other). Clip my fingernail, and I am
no longer the same individual I was before.
Knock me on the head and leave me catatonic and in a persistent vegetative
state, and I am no longer the same individual I was before. If we think that the latter change is more
fundamental than the former, and deprives me of my essence as a human being,
whereas the former change makes no difference, this is not because there is
any foundation in nature for this belief, but only because of the particular
resemblances we have chosen to abstract and have given names to. We only consider me to be human (as opposed
to “vegetative”) insofar as I am rational, and so we think that depriving me
of my rationality deprives me of something essential to my nature. But a knock on the head, which rearranges
my brain atoms, and the clipping of a fingernail, which separates some of my
fingernail atoms, are both equally motions that alter the previously existing
arrangement of the atoms that make me up and so are both equally changes in
the individual lump of material that I am.
It is just that the knock on the head alters something that we think has
to be present in order for this lump of material to be called by a certain
name, whereas the clipping of the fingernail does nothing to change the
applicability of that name. Locke captured this point by saying
that the essences we know and work with are merely “nominal.” That is, they are determined by the
definitions of the names we have chosen for our abstract ideas, definitions that themselves consist just of lists of those simple
ideas we have found to be common to our perceptions of a number of different
things, and selected from among a large number of other commonalities. (iv) However, if we understand the
term “essence” to refer to an Aristotelian substantial form or nature that
makes things of the same sort be like one another, or to refer to a definite
number of archetypes or blueprints that all existing things have been copied
from, then there are no such things as essences. Their existence is already called into
question, in Locke’s mind, by the existence of strange births or, as he put
it, monstrosities. As he saw it, were
it the case that each true sort of thing had its substantial form or nature,
common to all the members of that sort, and that this form or nature makes
all those members exhibit the same characteristics, then all things sharing
the same form or nature ought to be exactly identical, except for their
locations in space and time, and there ought to be no variations between
individuals of the same kind, and certainly no mutations in those kinds
capable of reproduction. Admittedly, there are ways to
reconcile essentialism with the occurrence of strange births. We need merely suppose that something
unusual happened to damage the substantial form or nature in the process of
its transmission from parent to offspring.
But Locke claimed that this is to build castles in the air. Even if there were such forms or natures,
we have no idea what they are, and no idea what might be responsible for
their being transmitted on some occasions and not on others. Rather than imagine that we arrange
individuals into sorts or kinds on the basis of their possession of some
supposed form or nature that we know absolutely nothing about, we should
recognize that all our classifications are based on our own abstract ideas,
which have been formed simply by collecting together those simple ideas that
a number of different substances share in common, apart from any knowledge of
what it may be in those individuals that is responsible for making us
perceive those simple ideas rather than any others. (v) Locke went on to admit that there
is undoubtedly some constitution of insensibly small parts in each thing,
responsible for making that thing give us the collection of ideas it
does. He referred to this as the “real
constitution” or “real essence” of a thing.
Whereas Aristotelian substantial forms or natures are hypothetical and
most likely non-existent, Locke was sure that real constitutions exist.
However, he also thought that real constitutions are not shared in common by
all the members of a sort or kind.
Each individual has its own real constitution, responsible for making
it that individual thing with all of its particular, individuating
characteristics and powers. This real constitution is different from the real
constitution of any other thing, however similar the two things may be. Of course, it would not be unreasonable to
suppose that the real constitutions of similar things might also be similar
(though the inference is not absolutely certain — just as differently
constituted clocks can still tell the same time, so different real
constitutions might well be responsible for the same manifest qualities and
powers in individuals). But because we
lack microscopical eyes, and so cannot see the
primary qualities of the insensibly small parts of bodies or determine how
these parts are arranged or moving, it follows that real constitutions,
together with any similarities there may be between them, are as unknowable
to us as Aristotelian substantial forms or natures. Thus, classification on the basis of
supposed similarities in real constitution is as impossible as classification
on the basis of the supposed possession of a common substantial form or
nature. Thus, all that we can base our
classifications upon are similarities in the collections of ideas that we get
from things when we look at them: that is, their nominal essences. This position on essences raises a
number of troubling questions. If the
real essence of each individual thing is itself individual, what accounts for
the fact that offspring resemble their parents? (After all, even granting the occurrence of
monstrosities, there is some
significant degree of this similarity across generations.) More broadly, what accounts for the
validity of general rules? Why is it,
if there are no common essences or natures in things, that dog bites should
produce rabies but not AIDS, or flea bites from infected rats bubonic plague
but not yellow fever? That certain diseases should be produced by certain
agents and not others, or, more generally, that certain effects should follow
from certain causes and not others, are simply broader versions of the same
question we ask when we ask why offspring share the characteristics of their
parents. If the real essence of every
distinct thing is what gives the things its powers, but the real essence of
every different thing is different, then how can we infer that same or
similar things will have same or similar effects? If we account for this by supposing that
similar things may have similar real essences (and there are indications that
Locke is willing to countenance this), then are we not saying that there may
be natural kinds after all, and that some classification schemes may be more
correct than others depending on whether they group objects by the true
commonalities in their real essences or not, even though we may not actually
be able to determine what the commonalities in the real essences are? These are questions that Locke
considered in more detail in Essay
III.vi. 24b Locke, Essay III.vi.1-9,12,14-19,23,25-26,28 Essence Locke’s main project in Essay III.vi is to undertake a more exact investigation of the nature of
the relation between the nominal
and the real essences of things. Recall that, according to the theory
of the meaning of general terms
presented in Essay III.iii, the
“nominal essence” of a thing is a
collection of simple ideas that are commonly perceived both in it and in a number of other things, and that
consequently have been abstracted
and referred to using a single name.
Thus, the nominal essence of
a human being is whatever collection of
simple ideas we form when we look at a number of human beings, notice that they resemble one another
in certain respects, form an
abstract idea just of these resembling features, and give that idea the name, “human.” There is nothing special about the name, nothing special about the individuals
we consider together, and nothing
special about the resembling features we pick out in those individuals. We may
pull a collection of individuals from anywhere
we please, consider them together, pull out any resembling features we please, and give the abstract idea so constructed any name we please. The only constraint on this operation is that the individuals we
consider together all have to
exhibit the resembling features we pick on, on pain of being ejected from the group, and any other
individuals also exhibiting the
features have to be admitted to the group.
But we can pick what
resembling features we want, give that abstract idea a name, and consider it to define a sort or kind
of thing. In contrast to the “nominal essence”
of a thing, which has to do with
what is contained in the abstract idea we form of its sort or kind, its “real essence,” or better, “real
constitution,” is the arrangement
of its insensibly small, solid, shaped, and moving parts. This
constitution gives the thing its power both to affect other things in the ways that it does and to bring about the ideas that it does in
us. It also literally constitutes the macroscopic primary
qualities of solidity, shape, size,
and motion of the thing. Crucially,
the real constitution does not just
bring about those few ideas that are included in the “nominal essence” of the thing, but all the ideas that we get when
we perceive it. That we only know the nominal essence and
not the real constitution of things
is a consequence Locke frequently remarked
upon in Essay III.iii and that
he took to be principally established
by the fact that we do not have microscopical
eyes. In Essay III.vi his main purpose was to establish a rather different and more surprising fact
about the relation between nominal
essences and real constitutions. This
is that our view of what qualities
and powers are necessary or “essential” to things can only be determined by the nominal essences of things and not by their real constitutions. Real constitutions are in principle incapable of serving as a basis for
the classification of things, even
apart from any reference to the fact that we know nothing about them. Indeed, far
from serving to sort things in to natural
kinds, the real constitutions of things are sorted into kinds by their nominal essences, and this is not merely a consequence of our ignorance of real
constitutions, but the way things
would be even if we knew the real constitutions. Those
features of the real constitutions of things that are essential to the things (the properly
denominated “real essences” of things)
are dictated by their nominal essences, so that nominal essence determines real essence and not the other way around. In drawing this conclusion Locke
deepened the anti-essentialist
conclusions of Essay III.iii. One could read Essay III.iii and still come away thinking that all that Locke had done was cast doubt on our
ability to know the real essences that
divide things in to natural kinds.
But, by the end of Essay III.vi
Locke had not just claimed that real essences are unknowable, but that they supply no ground for a “natural” division of things into kinds. Even today, it is possible to
appreciate something of the unsettling
character of Locke’s conclusions in Essay
III.iii and Essay III.vi when we
consider how appeals to natural kinds are
often invoked to justify positions on the rights of homosexuals, fetuses, or animals. But in Locke’s day, human beings themselves were considered to belong to
different kinds. This supposition supported the stratification of
British society into aristocratic and
common classes, fostered views of the inferiority of other races, and helped to justify
slavery. Locke’s attack on natural kinds supplied the epistemological
and metaphysical justification for
a radical republicanism that rejected these hierarchical views, and it helped to inspire and legitimate the American and French revolutions. QUESTIONS
ON THE
1. Locke observed
that what appears like a star to us may look like a sun to the inhabitants of distant planets. Why does
this show that our classifications of things into sorts depends on what complex ideas
we receive from them rather than on
natures or essences in things that make them what they are?
2. How did Locke
distinguish between real and nominal essence?
3. What is the
nominal essence of human being? the real essence?
4. What must be
the case before a particular individual can be considered to have an essence?
5. Can individual
particulars, considered just in themselves and apart from reference to any group, have real essences? why or why not?
6. Distinguish
between real essence and real constitution.
7. What
significance did Locke attach to the fact that we cannot explain why lead and iron are malleable, but antinomy and stones not, or why lead and antimony
are fusible, wood and stones
not? (Note that this question is based
on material that only appears in
the complete text of the Essay and
that is not found in Winkler’s
abridgment. For for
electronic copy of the complete text see the
instructions.)
8. What did Locke
mean by saying that there are no “chasms” or “gaps” in the visible corporeal world? (Note that he did not mean to deny that there is empty space or vacua.)
9. What
significance did Locke attach to the fact that different people understand the same kinds of things to have different nominal essences? 10.
If it is up to the understanding to construct
nominal essences, then why are
sheep-headed oxen and other fantastic arrangements
of complex ideas not considered to be nominal essences? NOTES
ON THE Locke’s position in Essay III.vi is striking. We naturally think that since it is the real constitution of things that
makes them what they are, that same
real constitution ought to sort them
into true or natural kinds, whereas their nominal essences are merely arbitrary or conventional
inventions of the understanding,
which has chosen, with dubious validity, to notice and abstract certain resemblances between things and not
others. But that the real constitutions should not only not
determine natural kinds, but be themselves
sorted into kinds by the nominal essences may appear extraordinary. How could
Locke both grant that there are real constitutions
and yet take the merely nominal essences to be what determines the properly essential features of these real constitutions? Locke offered a single, but
multi-layered argument for his position
over the course of Essay III.vi. The argument opens by first
establishing a preliminary point: that
there is nothing essential to individuals considered just as individuals. To establish this point, Locke
observed that if you do not consider
what kinds an individual might or might not belong to, but simply consider it on its own, then it appears as a unique individual and any change whatsoever,
however minuscule, is a change in
that individual nature, and turns it into something different from what it was before. In other words, everything that an individual has in it — all of
its qualities and powers — are
equally essential to its individual nature.
But to say that all the qualities and powers of an
individual’s nature are essential
is tantamount to saying that none
are. For, if everything is essential, then nothing is accidental, and if nothing is accidental, then it does
not mean anything to call a quality
essential, since there is no contrast implied with anything non-essential. It is only when individuals are
considered as belonging to some
kind or other that some of their qualities and powers acquire the status of being essential as opposed to accidental. If an individual belongs to a kind,
then we can say that loss of the
qualities or powers characteristic of that kind would change the thing in kind whereas loss of any
other qualities or powers would
still leave it the same kind of thing.
This creates the difference
between “essential” and “accidental” qualities. But this also means that an individual
must be considered to belong to a
kind before it can be considered to
have an essence. Having established these preliminary
points, that nothing is essential
to individuals, and that individuals must be
considered to belong to a kind
before any of their qualities or powers can be considered essential, Locke proceeded to his main argument. How,
he asked, do individuals come to be of a sort or kind? It cannot be, he claimed, in virtue of
their real constitutions, since the
real constitution of each individual is
different. Each distinct thing has
its own real constitution, so classifying
things by their real constitutions would force us to recognize as many classes of things as there are individuals and would get us nowhere. But if we cannot know the real
constitutions of things, how can we
claim to know that they are different in each different thing? Locke had some
things to say by way of answer to this question,
but before considering them it is worth while to digress briefly to mention a
background consideration. While Locke thought that we cannot
know exactly what the real constitutions
of things are, his position in Essay
II.viii.7-26 is that we can know
that they have real constitutions, and that we can know that these real constitutions consist of some sort
of arrangement of insensibly small,
solid, shaped and moving particles. We just cannot know exactly what
arrangement. Moreover, we can know that all the manifest
qualities of things (their macroscopic
primary qualities and observable powers) supervene on their real essences.
Otherwise put, Locke conceived of the real constitution as responsible for building up the
visible or macroscopic primary qualities
of a thing, and for giving it all of its powers to affect other things and bring about type (i),
(ii) and (iii) ideas in us. Since the real constitution brings about
the manifest qualities, we can
suppose that wherever the set of manifest
qualities is different, there must be some difference in the real constitution.
(Otherwise, the real constitution would not account fully for why the manifest qualities are the way
they are. If the same real constitution could bring
about different sets of manifest
qualities in different things, then there would have to be something more at work than just that real constitution to explain why the
qualities are different when the real
constitution is the same. But, ex hypothesi,
the real constitution is supposed
to be what alone produces the manifest qualities.) But while we can infer that different
sets of manifest qualities and
powers indicate a difference in the real
constitution of things, we cannot infer that identical manifest qualities and powers are produced by
identical real constitutions. Just as there are many ways to build a
clock that will still tell the same
time, so many different real constitutions
could conceivably be responsible for giving a thing the same manifest primary qualities and powers. Thus, the most that an observed similarity in manifest qualities and powers could do is establish the possibility
of a similarity in underlying real
constitutions, not prove that there must be such a similarity. Whenever the members of two sets, call
them S and U, are related in such a
way that no two different members of S could be correlated with a single member of U, but two or more members of U could be correlated with the same
element of S, then S is said to
supervene on U. In the case at hand,
the elements of S, the supervenient set, are the collections of manifest
qualities and powers characteristic
of things, and the elements of U, the subvenient
set, are the real constitutions those things could possibly have. Since
differences in the manifest qualities and
powers of things imply differences in their underlying real constitutions, no two members of S
could be correlated with (or, in
this case, caused by) the same member of U.
But since the same
collection of manifest qualities and properties may be produced by different real constitutions, two or more members of U may be correlated with the same
member of S. This is why it can be said that, for Locke, the
manifest qualities and powers of things
supervene on the real constitutions of things, whereas those real constitutions underlie or subvene
their manifest qualities and
powers. With these remarks on the nature of
the supervenience relation between manifest qualities and powers in objects and their underlying real constitutions in
mind, let us return to Locke’s reasons
for saying that each individual thing has its own real constitution. As Locke noted at Essay III.vi.8, however similar the members of a certain sort or kind may be in some respects, they always differ significantly from one another
in other, so-called “accidental”
respects. Even different lumps of
gold, sulfur, antimony, or vitriol,
Locke thought, do not all have exactly the
same qualities or powers. Robert
Louis Stevenson’s The Strange Case of
Dr. Jekyll and Mr. Hyde was, over a century later, to offer an apt
illustration of this point. Jekyll, as
the story goes, was able to concoct a potion that separated the good from the
evil parts of a human being. But to
his dismay, he was only able to make one lot of the potion. All subsequent efforts at replicating the
recipe failed, despite the chemists’ assurances that they had provided him
with the purest samples of his ingredients.
It finally came to his mind that the original potion had only worked
because one of the ingredients had contained some impurity. As far as Jekyll was concerned, it was that
impure sample that expressed the real essence of the substance he wanted to
use in his recipe. Unfortunately, no
one was attempting to refine that sort of material, so it had only been
produced by accident and mistake, meaning that the art of replicating further
samples was inaccessible. The story nicely illustrates Locke’s
distinction between the real constitution and the real essence of a
thing. The real constitution of an individual thing is that arrangement
of insensibly small, shaped, solid,
and moving parts that is responsible for all
of its qualities and powers. The real constitution does not just produce those qualities and powers in
the thing that are considered
essential, or that we suppose characterize it in its “pure” form, but also those that are accidental, or that we
think that are only present because
of the “impurities” the particular sample
of the material we are studying contains.
The real essence, in contrast, is just that part of the real
constitution that is responsible for producing those ideas we get from the
thing in its “pure” form. But nothing
exists in just a pure form. Every
sample of a material differs from every other sample of that material in some
way. Since there are different
“accidental” qualities and powers in individuals
of the same species, and since differences in the supervenient qualities and powers
indicate differences in the underlying
real constitutions, the real constitutions of different individuals of the same species must be different from one another as well. It might be objected that even if we
grant this point, it still only
follows that we could not consider the whole
of the real constitution of an
individual thing to be what determines its
membership in a sort or kind. But
might we not still be able to take
a part of this constitution to do
the job? After all, if the real constitution is what is
responsible for the entire collection
of ideas we get when we perceive a particular thing, and the collection of simple ideas we get when we perceive one particular contains some ideas in
common with the collection we get
when we perceive another particular, then it is at least possible that this agreement in manifest qualities is due to the individuals having some commonalities
in their real essences. Admittedly,
the inference from similarities in supervenient, manifest qualities and powers back to
similarities in underlying, unknowable
real essences is uncertain. But surely
it is at least possible that an
underlying similarity in real essences accounts
for the manifest similarity in supervenient qualities and powers. Were there such a thing, it would certainly deserve to be considered an
essential part of the real constitutions
of things, or a “real essence.” Locke had two main reasons for
dismissing this fall-back position. One rests with an appeal he already made at
the close of III.iii to the
existence of mutations or “monsters.”
Were all the members of a
species to possess a common, fixed, “real
essence” that they transmit to their offspring, then it would be a mystery why mutations occur. This is especially the case if the mutations are random and not caused by any apparent interference with the usual process
of generation, and if they are
viable, capable of reproduction, and possessed of their own special adaptations and powers, so
that they cannot simply be dismissed
as incomplete or defective copies that only lack some of what was in their parents due to some interference with the generative process. In this case, Locke speculated, it is much more plausible to attribute mutations
to the emergent effect of subtle
but important differences in the supposedly common “real essences” of the parents, rather than hold to the supposition that the real essences are identical
in all the members of the species. Locke’s second reason rests on an appeal
to evidence for the existence of a
through-going continuity in the species of
things. Between any two species of
animal, vegetable, or mineral, we
have so often found there to be intermediate species (Locke mentioned flying fish, fishy-tasting birds, sea mammals, amphibians, and even mermaids) that
it is a reasonable induction that
somewhere in the heretofore unexplored parts of the world, or perhaps on other planets, there
will be found some species that is
intermediate between any two given species whatsoever. Moreover, even within species it is often obviously the case
that there are individual
variations that make some members of one
species look so similar to some members of another that they could almost be seen to have more in
common with members of the other
species than with members of their own.
But, if we are going to
allow inferences from similar manifest qualities back to similar real essences, then by parity of argument we are going
to have to allow that the
continuity of species indicates an underlying
continuity in the real essences of things.
But on a continuum all
divisions are arbitrary. Just as a
line may be cut at any point along
its length, or cut into as many different
segments as one pleases, so a continuum of real essences for different forms of life could be
divided into arbitrarily many different
species and there would be nothing in the real essences to mark where the divisions ought to go. Let us sum up the course of this
rather long chain of argument. Locke’s claim is that it may well be that,
if a group of individuals all bring
about the same collection of simple ideas
in us, then the real constitutions of those individuals will have some “real essence” in common. But given the variance of individuals within species, the occurrence of mutations, and the continuity of species, it is
likely that the real constitutions
of all individuals are similar to the real
constitutions of all other individuals in some way or other, and that there are no sharp breaks or
gaps in the continuum of varying
real constitutions that might justify drawing a demarcation between species in one place rather than another. Of course, this does not present an
impediment to our ability to
classify things, since our classifications could never have been based on anything we discerned
in the real constitutions of things
in any case, given that we cannot perceive those constitutions.
Nonetheless, the fact that there is nothing in the real constitutions of things to justify classifying things
in one way rather than another
leads to an ironic result: that the classification
of essential components of real constitutions or “real essences” depends on our identification of nominal essences. It is by attending to and abstracting
certain resemblances in the collections
of ideas we receive from things (certain
nominal essences) and ignoring others that we privilege certain possible similarities in the underlying real constitutions as “essential” and
dismiss others as “accidental.” Had
we chosen to focus on other similarities, abstracted a different idea of those similarities, and made that into the nominal essence of a species, then a different collection of the similarities in the real constitutions of things would have been picked out as “essential.” Thus, it is the nominal essences that determine the real essences, or
better, that determine those features
in the real constitutions of things that we pick out as essential) rather than the other way around. And that is just Locke’s point in Essay
III.vi. This ultimately conventionalist
position on our knowledge of the
sorts or kinds of things is once again one that had disturbing implications for many of Locke’s contemporaries. These implications went beyond the
republican ones mentioned earlier. In discussing the continuity of species,
Locke remarked that there may be as
many different sorts or kinds of thinking
things as there are of bodies. But
between the lines of this remark
was the suggestion that there may also be a continuity between the species of spirits and of
bodies, as well as between spirits
and other spirits or bodies and other bodies.
Might that mean that there
is no sharp line to be drawn between mind and body? And if the way we
classify things into sorts or kinds has
no ultimate foundation in commonalities in the real essences of different things — or rather, if any
classification system whatsoever
could be found to have some foundation in some commonalities or other in the real essences of things (which is to say the same thing) — then what about
the distinction between minds and
bodies itself? Might that be equally
merely nominal? In Essay
III.vi these are merely disturbing questions, and yet further indications of a systematic program, initiated in the chapter on substance, advanced in the
chapter on identity, and yet
further prosecuted here, to undermine the foundations of the distinction between mind and
body. Locke was to declare himself yet more fully on this topic in Book
IV, with a passing remark on the possibility
that matter could be made to think that made his intentions fully explicit and ignited a storm of controversy. COMMENTARY
ON THE TEXT At the close of the previous chapter,
a number of troubling questions
were raised about Locke’s position on essences and universals. We are now in
a position to see how Locke might have answered those questions. That similar causes should have similar effects, and in particular that in
generation effects should also resemble
their causes (as offspring resemble their parents) is something Locke could have explained by allowing that there may
well be similarities in the real
constitutions of causes — similarities that
lead to similar effects in their interaction with other things, and that are transmitted to their progeny in generation. But this does not mean that there is
an ultimate foundation for classification
after all, for there is a flip side to this observation. Just as
similarities in the real constitutions of
things of a certain kind may be what accounts for the fact that all of those things tend to have
similar effects, so dissimilarities
in the real constitutions of those same things are certainly what accounts for the fact that not all of those things behave in exactly the same
way. (And however similar two individuals may be in some effects
and behaviours, they are always
dissimilar in others.) The fact is
that just as all things can be
found, with a bit of ingenuity, to resemble any other thing in some way or other, so all things can be found, with a bit of ingenuity, to behave
like any other thing in some way or
other. And just as we have chosen to
notice certain resemblances in
qualities while ignoring others when forming our abstract ideas of the sorts of things, so we have chosen to notice certain resemblances in powers
while ignoring others. By focusing on certain powers while
ignoring others, we in effect focus
on certain possible commonalities in the real constitutions of things while ignoring others. Thus, here too, it is the nominal essences (the manifest powers
in things that we choose to notice)
that determine the real essence (or those conjectured commonalities in the real constitutions of different things that we choose to consider essential), and
not the other way around. ESSAY
QUESTIONS AND RESEARCH TOPICS
1. In the
Introduction to his Principles of human
knowledge of 1710, George Berkeley attacked Locke’s account of abstract
ideas. Study
2. For Locke, the
meaning of a word is the idea it is used to name. Ideas are also private
mental occurrences, known only by the person who has them. This means that everyone’s language is
private, the words in it being used to refer to things that only that person
knows. The intelligibility of a
private language was famously attacked by Ludwig Wittgenstein, Philosophical investigations (Oxford:
Blackwell, 1953), p.269ff. Recount
Wittgenstein’s argument and determine (i) whether
Locke’s account of language is ultimately a “private language” account or
rather an account that recognizes that meaning is ultimately determined by
factors external to the individual’s mental states, and (ii) whether Locke’s
account can be defended against Wittgenstein’s attack.
3. At the outset
of the Investigations Wittgenstein
attacked the traditional Lockeian account of
classification on the basis of observed similarities and proposed an
alternative account of how it is that we group things like dogs together by
appeal to the notions of a language game and of family resemblance. Outline Wittgenstein’s account and
determine whether it is superior to Locke’s.
Does Locke’s view that we might classify objects on the basis of their
tertiary qualities or powers provide him with a way of evading Wittgenstein’s
criticisms of the traditional account?
4. Has Locke’s
conventionalism about real essences been refuted by modern chemistry?
(That is, do modern definitions of the elements in terms of the numbers of protons in their nuclei constitute definitions in terms of
“real essences” that are not merely
conventional, but grounded in nature?)
In giving your answer, you
should consult the discussion of this issue in Michael Ayers, Locke,
epistemology and ontology, 2 vols. (London: Routledge, 1991), vol. II, ch. 7, pp.
78-90, drawing on earlier work by
Saul Kripke, “Naming and Necessity,” in Donald
Davidson and Gilbert Harman, eds., Semantics of natural language (Dordrecht,
1972), and Hilary Putnam, Philosophical
papers II: mind, language and reality (Cambridge: Cambridge University Press, 1975). |