Particulars Are Real
Classic Philosophical Questions Part 6 - Metaphysics
David Hume, from An Enquiry Concerning Human Understanding
Kem Stone - 6 January 2008
The idea that universals really exist and that any particular object is merely a subspecies of one of these universals
is strongly refuted by David Hume in this text, which provides several compelling arguments in favour of the
position that reality consists only of particular objects and that the concept of universals is merely a side-effect of
language.  That this is the correct position on this issue seems completely obvious to me, but Hume’s arguments
provide a strong logical support for the opinion that scientific knowledge has already led me to adopt.

Hume does not claim credit for this position, but actually cites Berkeley’s assertion that “all general ideas are
nothing but particular ones annexed to a certain term, which gives them a more extensive signification and makes
them recall upon occasion other individuals which are similar to them” (346) in order to introduce the idea.  For
example, the abstract idea of “a man” represents men of all shapes, sizes, and qualities, but of what does this idea
actually consist when present in the mind?  It cannot possibly contain within it ideas of men of all possible sizes
and qualities, or the mind’s capacity would be infinite, and it is plainly obvious that this is not the case.  On the
other hand, it may not represent any particular man at all, and it is this conclusion that has led many to believe that
our abstract ideas do not contain any particular degree of quantity or quality.  This is the conclusion that Hume
sees as erroneous, and which he sets out to disprove in two ways: first by proving one cannot conceive of a
quantity or quality without also forming a precise notion of its degrees, and second that the mind does not need to
have an infinite capacity in order to form a notion of all possible degrees of quantity and quality.

Hume gives three arguments to support his first proposition: that the mind necessarily conceives of precise degrees
when considering quantity and quality.  We know that any objects that are different are distinguishable, and
whatever objects are distinguishable are separable in thought.  “In order therefore to know whether abstraction
implies a separation, we need only consider it in this view, and examine whether all the circumstances which we
abstract from in our general ideas, be such as are distinguishable and different from those which we retain as
essential parts of them.  But ‘tis evident at first sight that the precise length of a line is not different nor
distinguishable from the line itself, nor the precise degree of any quality from the quality.  These ideas, therefore,
admit no more of separation than they do of distinction and difference” (346).  Although the general idea of a line
may not inherently have a precise length, the line that is present to our imagination when we conceive of this
general idea does, and in fact
must have, a precise degree.

This leads to Hume’s second argument, that no object can be perceived by the senses and thus present to the
mind without a precise determination of its quantity and quality.  The confusion as to this issue is merely the result
of the unsteadiness or faintness of the ideas that result from these impressions, not from any capacity in the mind to
receive an impression without precise proportions.  Because all of our ideas are representations of impressions of
real objects, and since all real objects have particular proportions, so too must our ideas have these proportions.  
An idea is nothing more than a weaker impression, so what is true of the impression must be true of the idea.

Hume’s third argument asserts not just the lack of the mind’s capacity to conceive of an object without particular
proportions, but the
impossibility of any such conception to be formed.  It is absurd, says Hume, to suppose that
a triangle exists which has no precise proportion of sides and angles.  Because this is absurd
in fact it must also
be absurd
in idea.  Nothing of which we can form a clear and distinct idea is absurd, but we can not form a clear
and distinct idea of a triangle without precise proportions.  We can conceive of the
idea of such a triangle, but it is
impossible to
picture it.  Any triangle we do picture will have precise degrees—the mind cannot picture an
absurdity.  “Now as ‘tis impossible to form an idea of an object that is possessed of quantity and quality, and yet
is possessed of no precise degree of either, it follows that there is an equal impossibility of forming an idea that is
not limited and confined in both these particulars.  Abstract ideas are therefore in themselves individual, however
they may become general in their representation” (347).  So while we may hold in our mind an image of one
individual object to represent all similar objects, the idea we have is necessarily a representation of only
particular object.

Hume now turns to his second proposition, which is that the mind can form a notion of all possible degrees of
quantity and quality of any object without explicitly imagining all such variations.  This is a result of our use of
language, which uses one word to represent many similar objects in spite of their differences.  “When we have
found a resemblance among several objects that often occur to us, we apply the same name to all of them,
whatever differences we may observe in the degrees of their quantity and quality, and whatever other differences
may appear among them.  After we have acquired a custom of this kind, the hearing of that name revives the idea
of one of these objects and makes the imagination conceive it with all its particular circumstances and proportions”
(347).  Although we use the word “table”, for instance, to represent all tables, the image we form in our mind is of
only one particular table, with all its particular proportions.

A perfect illustration of how the mind uses a particular word to represent a universal concept is the word “triangle”
which usually conjures the image of an equilateral triangle in the mind.  Yet upon forming this image, should we
make the false assertion that all three sides and angles of a triangle are always equal, the mind will conjure up
images of a scalenum or isosceles triangle to show what we have overlooked—that not every triangle is the
equilateral that we imagine upon first hearing the word.  Furthermore, the mind may sometimes run over several
different images before resting on the intended meaning of a word.  The word “figure” will raise up images of a
square, rectangle, circle, etc. to represent this word, all of which are individual and particular although the word
itself in reality represents an infinity of possible objects.  “
Some ideas are particular in their nature, but general
in their representation
.  A particular idea becomes general by being annexed to a general term; that is, to a term
which from a customary conjunction has a relation to many other particular ideas, and readily recalls them in the
imagination” (348).

Finally, Hume deals with another source of confusion regarding the existence of universals, which has to do with
the “distinction of reason” between such concepts as figure and body figured, motion and body moved.  Because
we know that any ideas which are different are separable, it should follow that if a figure is different than the body
figured, figure must be a separate and distinguishable, and therefore universal, concept.  But Hume shows that the
ideas are not as separable as such logic would suggest.

If we are presented with a globe of white marble, we have only the impression of a white colour in a certain form,
which cannot immediately be distinguished.  It is only if we are also presented with a globe of black marble or a
cube of white that we now have the ability to make the distinction.  “When we would consider only the figure of
the globe of white marble, we form in reality an idea both of the figure and colour, but tacitly carry our eye to its
resemblance with the globe of black marble.  And in the same manner, when we would consider its colour only,
we turn our view to its resemblance with the cube of white marble” (349).  It is impossible to conceive of a colour
without form, or a form without colour.  These ideas are only separate and distinguishable when manifested in
particular objects that share a certain form or colour and thus allow us to draw out the similarities by using a word
that supposedly represents a universal concept, when in reality it only applies to a finite multitude of the things we
have experienced and have used that word to represent.

I of course agree with Hume, and do not see any flaws in his arguments.  My own reasons for disbelieving in the
existence of universals, which I out-lined in my reaction to Plato’s theory of Forms, are scientific rather than
logical.  All objects in the universe are composed of particles assembled into different configurations, whether it is
a rock, a tree, a star, or a person.  None of these configurations are exactly alike, but we use certain words to
group these individual objects into classes, which leads to the idea that there really is a universal “Rock”, “Tree”,
“Star”, or “Person.”  But in reality no two rocks, trees, stars, or people are exactly alike and each exists as a
unique and particular object.  Hume’s arguments show how the mind’s use of a single word to represent similar
objects leads to the false idea that universals exist, and that a mental image of one particular object is sufficient to
represent the concept of all related objects.  Most importantly, one cannot even conceive of what a universal
anything would look like, and because the image of one particular object is sufficient to represent all objects of
the same name, it is unnecessary to postulate the actual existence of universals.