Thursday, 26 January 2017


"John Locke. The discussion of abstraction which is
 perhaps most familiar to modern readers is to be found
 in Locke's Essay Concerning Human Understanding.

Words become general by being made the signs of general
ideas; and ideas become general by separating from them
the circumstances of time and place, and any other ideas
that may determine them to this or that particular existence.
By this way of abstraction they are made capable of repre-
senting more individuals than one; each of which having
in it a conformity to that abstract idea, is (as we call it)
of that sort
(Book III, Ch. 3, para. 6).
He goes on to suggest immediately that nothing new
is introduced in this process but that it is rather a
process of omitting all individuating features, and re-
taining only what is common to all of a set of resem-
bling particulars. This omission, he explains elsewhere
(Book II, Ch. 13, para. 13), is a kind of partial consid-
eration which does not imply a separation. But Locke
applies the notion of abstraction to cases which go
beyond the mere omission of particular spatiotemporal
determinations. In the famous example of forming the
general idea of a triangle, Locke says that this idea
of triangle in general is “something imperfect that
cannot exist, an idea wherein some parts of several
different and inconsistent ideas are put together” (Book
IV, Ch. 7, para. 9). Whatever Locke may have thought
this “putting together” amounted to, it is certainly not
achieved simply by omitting particularizing features
of several particular triangles. The fact is that no single
doctrine of abstraction can be found in Locke, as
I. A. Aaron has shown (Aaron, 1937).

Berkeley and Hume. Berkeley's critique of abstrac-
tion proceeds along lines which were relatively new
to his readers but which had already been worked out
by Al-Ghazali in the eleventh century and even by
Ockham in the fourteenth century. If two things (in
Berkeley's philosophy, of course, two ideas) can exist
separately, the mind can abstract one from the other.
But if it is granted that two things cannot exist one
apart from the other, i.e., that there would be a con-
tradiction if a were supposed to exist without b (or
conversely), the mind cannot think of a without b or
of b without a. To argue otherwise would be to attrib-
ute to the human mind a power which not even God
can be supposed to have or exercise.

Hume adopted Berkeley's critique and elaborated
a positive theory of the function of general terms which
goes beyond Berkeley. Although every idea is particu-
lar, some ideas can function as general ones by being
associated with a name of a number of particulars
which resemble one another exactly or only approxi-
mately. In the latter case, the name is associated with
a number of qualitatively different but resembling
images. One of these associated images will be domi-
nant, the others relatively recessive but, as Hume puts
it, “present in power to be recalled by design or neces-
sity.” Thus, although a red image may be recalled when
the word “color” is pronounced, heard, read, or re-
called, other color-images less strongly associated with
the word “color” tend to appear in consciousness, are
“present in power,” and will be recalled if there is
danger of a mistakenly narrow use of “color” present-
ing itself. This then, is Hume's alternative to the doc-
trine that there are either genuine images or abstract
general ideas. The traditional explanation of the ori-
gin of abstract concepts persisted, with some modi-
fications, among the philosophers of the eighteenth

A considerable advance in the understanding of the
nature and function of concepts seems to have been
made by Immanuel Kant. The verb, adjective, and noun
frequently occur in Kant's Critique of Pure Reason
(Werke, A54, A70 [B95], A76, A96) without any special
explanation. But Kant's doctrine of pure as well as a
posteriori concepts leaves no doubt that abstraction
alone cannot account for the existence or employment
of concepts (Werke, VII, 400-01). “The form of a
concept, as a discursive representation is always con-
structed.” As Kant puts it in the Prolegomena to any
Future Metaphysics (para. 20), empirical concepts
would not be possible unless a pure concept were
added to the particular concept which has been ab-
stracted from intuition. And, finally, in the Critique of
Pure Reason, the concept is presented as a rule by
means of which the imagination can outline, for exam-
ple, the figure of a certain quadruped (say, a dog)
without limiting it to such a determinate figure as one's
experience or concrete images might present. Kant
calls this a schema. Without such a schema (which is
an application of the pure concepts of the understanding)
neither images nor a conceptualization of images would
be possible.

Kant's doctrine that pure concepts, i.e., the cate-
gories of the understanding, be at the basis of all con-
ceptual thinking thus makes the process of abstraction
subsidiary to and dependent upon faculties which are
logically prior to any process of abstraction from em-
pirical data. As more than one writer has recently
pointed out, empirical concepts are more like disposi-
tions than like static constituents of consciousness.
There is, however, no suggestion in Kant that abstrac-
tion does not occur. That this new view of the activities
of the mind would require an entirely different account
of abstraction is not made very plain in Kant's writings.

In the development of metaphysical Idealism in the
post-Kantian philosophers, the notion of abstraction
becomes very general, so general in fact that the origi-
nal meanings of the term seem almost lost. What makes
the matter even more difficult to discuss is the fact
that, among these Idealists, any separation or isolation
of one content or feature of experience or thought from
another is condemned as falsification, so that “to ab-
stract,” “abstract,” “abstraction,” all acquire a pejora-
tive sense. To separate the cognizing subject from its
object, to attend to one discriminable element apart
from its surrounding, and the like, are all condemned
as falsifications of reality. This condemnation rests on
the Hegelian doctrine that “the Truth is the Whole,”
i.e., that all aspects of thought and reality are 
dialectically interconnected.

Other more significant attacks on the doctrine that
general concepts result from abstraction come from
Husserl's thorough critique of Locke and his eight-
eenth-century critics. While insisting on the absurdity
of Locke's doctrine, Husserl attacked with equal vehe-
mence the theories of Berkeley, Hume, and Mill. He
insisted that the general attributes are given to con-
sciousness initially, and thus repudiated the traditional
doctrine of abstraction. There are similar views to be
found in some of the writings of Whitehead and San-
tayana. The “eternal objects” of Whitehead and the
“essences” of Santayana are supposed to be discoveries
rather than constructions; they are not the results of
creations of mental activities, and thus are not the
result of abstraction as it was traditionally expounded,
although the accounts of abstraction in terms of atten-
tion and comparisons would be consistent with such