Written by Ephraim Chambers   
Thursday, 01 January 1728 09:00
an Operation of the Mind, whereby we separate Things naturally conjunct, or existing together ; and form and consider Ideas of Things thus separated. See ABSTRACT.

The Faculty of Abstracting, stands directly opposite to that of Compounding — By Composition we consider those Things together, which in reality are not join'd together in one Existence. And by Abstraction, we consider those Things separately and apart, which in reality do not exist apart. See COMPOSITION.

Abstraction is chiefly employ'd these three ways— First, when the Mind considers any one Part of a Thing, in some respects distinct from the Whole ; as a Man's Arm, without the Consideration of the rest of his Body.

Secondly, when we consider the Mode of any Substance, omitting the Substance it self; or when we separately consider several Modes which subsist together in one Subject. See MODE.

This Abstraction the Geometricians make use of, when they consider the Length of a Body separately, which they call a Line ; omitting the Consideration of its Breadth and Depth.

Thirdly, it is by Abstraction that the Mind frames general or universal Ideas ; omitting the Modes and Relations of the particular Objects whence they are form'd. — Thus, when we would understand a thinking Being in general, we gather from our Self-consciousness what it is to Think ; and omitting the Consideration of those Things which have a peculiar Relation to our own Mind, or to the human Mind, we think of a thinking Being in general.

Ideas fram'd thus, which are what we properly call Abstract Ideas, become general Representatives of all Objects of the same Kind ; and their Names applicable to whatever exists conformable to such Ideas. — Thus, the Colour that we receive from Chalk, Snow, Milk, &c. is a Representative of all of that Kind ; and has a Name given it, Whiteness, which signifies the same Quality, wherever sound or imagin'd. See GENERAL.

'Tis this last Faculty, or Power of Abstracting, according to Mr. Locke, that makes the great Difference between Man and Brutes ; even those latter must be allowed to have some share of Reason : That they really reason in some Cases, seems almost as evident as that they have Sense ; but 'tis only in particular Ideas. They are tyed up to those narrow Bounds ; and do not seem to have any Faculty of enlarging them by Abstraction. Essay on Human Understanding, L. III. c. 3.

Such is the Doctrine of Abstract Ideas, under the Improvements of that excellent Author. In effect, 'tis the standing Opinion, that the Mind has such a Power or Faculty of framing Abstract Ideas or Notions of Things ; and on such very Ideas do a great part of the Writings of Philosophers turn. These are supposed in all their Systems ; and without them there would be nothing done. — They are more especially reputed the Object of Logick and Metaphysicks, and all that passes under the Notion of the mott abstracted and sublime Learning.

Yet has a late eminent and ingenious Author, Dean Berkeley, contested the Reality of any such Ideas ; and gone a good way towards overturning the whole System, and consequently towards setting our Philosophy on a new footing.

The Qualities or Modes of Things, 'tis on all hands agreed, do never really exist apart, and separated from all others ; but are constantly mix'd and combin'd together, several in the same Object. — But, say the Philosophers, the Mind being able to consider each Quality singly, or abstracted from other Qualities with which it is united, does by that meansframe to it self Abstract Ideas, of a different Nature and Kind from the sensible ones.

For an Example hereof, The Eye perceiving an Object extended, coloured, and moved, resolves this Compound Idea, into its simple, constituent ones ; and viewing each by it self, exclusive of the rest, frames Abstract Ideas of Fxtension, Colour, and Motion themselves, or in their own Nature. — Not that it is possible for such Colour and Motion to exist without Extension ; but only that the Mind can frame to it self, by Abstraction, the Idea of Colour exclusive of Extension; and of Motion, exclusive both of Colour and Extension.

Again, say the same Philosophers, the Mind having observ'd that in the particular Extensions perceived by Sense, there is something common, and alike in all ; and some; other things peculiar ; as this, or that Figure or Magnitude, which distinguish them one from another ; it can consider apart, or single out by it self, what is common ; making thereof a general abstract Idea of Extension, which is neither Line, Surface, nor Solid, nor has any Figure or Magnitude, but is an Idea entirely prescinded from 'em all. -

So, likewise, by leaving out of the several Colours perceived by Sense, that which distinguishes them from one another, and only retaining what is common to all, it makes an Idea of Colour in the Abstract, which is neither red, nor blue, nor white, &c. —
After the same manner, by considering Motion abstractedly, both from the Body moved, and from the Figure it desribes, and all particular Directions, and Velocities ; an Abstract Idea of Motion is framed, which equally corresponds to all Motions whatever.

They add, that as the Mind frames Abstract Ideas of Qualities or Modes ; so does it, by the same Faculty, attain Abstract Ideas of the more compound Beings, which include many coexistent Qualities. - For an Example — Having observ'd that Peter, James, John, &c. resemble each other in Shape, and other Qualities ; we can leave out of the Complex Idea we had of Peter, James, &c. that which is peculiar to each, retaining only what is common to all, and so make an Abstract Idea, wherein all the Particulars equally partake. -

And thus is is we are supposed to come by the Abstract Idea of Man, or of Humanity, or Human Nature ; wherein there is indeed included Colour, because no Man but has some Colour, but it is neither white, nor black, nor brown ; because there is no one particular Colour wherein all Men partake. So likewise there is included Stature, but then it is neither tall, nor low, nor yet middle Stature, but something abstracted from all these : And so of the rest.

Farther yet, there being a general Variety of other Creatures, which partake in some Parts, but not all, of the Complex Idea of Man ; the Mind leaving out those Parts which are peculiar to Men, and retaining those only which are common to all living Creatures, frames the Idea of Animal ; which abstract s or participates not only of all Men, but all Birds, Beasts, Fishes, and Insects.

The constituent Parts of such Abstract Idea of Animal, are Body, Life, Sense, and spontaneous Motion. —
By Body, is meant, Body without any particular Shape, or Figure ; there being no one common ro all Animals ; without Covering, either of Hair, of Feathers, or Scales : nor yet naked ; Hair, Feathers, Scales, and Nakedness, being the distinguishing Properties of particular Animals, and for that Reason left out or the Abstract Idea. Upon the same Account, the spontaneous Motion must be neither walking, nor flying, nor creeping ; it is nevertheless a Motion —
But what that Motion is, it is not easy to conceive.

« I will not affirm, says Dr. Berkeley, that other People have not this wondersul Faculty of abslratl'wg their Ideas ; but I am consident I have it not my self. —
I have, indeed, a Faculty of imagining, or representing to my self the Ideas of Things I have perceived, and of variously compounding or dividing them : I can imagine a Man with two Heads, or the upper Parts of a Man join'd to the Body of a Horse. I can consider the Hand, the Eye, the Nose, each by it self, abstracted or separatcd from the rest of the Body —
But then, whatever Hand or Eye I imagine, it must have some particular Shape and Colour. —
So, again, the Idea of a Man Iframe to my self, must be either of a white, or a black, or a tawny, a strait or a crooked, a tall, or a low, or a middle-fiz'd Man. »

« I cannot by any Essort of Thought conceive the Abstract Idea above described ; and it is equally impossible for me to form the Abstract Idea of Motion, distinct from the Body moving, and which is neither swift nor slow, curvilinear, nor rectilinear. —
And the like may be said of all other abstract general Ideas whatever. »

Since all things that exist are only Particulars,
« Whence », says Mr. Locke, « is it, that we come by general Words, expressive of a thousand Individuals ?»
His Answer is, « Terms only become general, by being made the Signs of c absiratl and general Ideas ;»
so that the Reality of Abstract Ideas, should follow from the Reality of General Words. But this is a Deception. —
A Word becomes General, by being made the Sign, not of an abstract general Idea, but of several particular ones ; any one of which it indifferently suggests to the Mind.—
For an Example, when I say that Whatever has Extension is divisible ; the Proposition is to be understood of Extension in general ; not that I must conceive any abstract general Idea of Extension ; which is neither Line, Surface, nor Solid, neither great nor small, &c.

To make this more evident, Suppose a Geometrician to be demonstrating a Method of dividing a Line in two equal Parts : In order hereto, he draws, for instance, a black Line, an Inch long ; and this, which in it self is a particular Line, is nevertheless, with respect to its Signification, general ; since it represents all Lines whatever : So that what is demonstrated of this one, will hold of all others —
And as that particular Line becomes general by being made a Sign ; so does the Name Line : And as the former owes its Generality, not to its being the Sign of an abstract or general Line, but of any or all particular right Lines that may possibly exist ; so must the latter derive its Generality from the same Cause. See GENERAL Term.

Mr. Locke, speaking of the Difficulty of forming Abstract Ideas, says :
« And does it not require some Pains and Skill to form the general Idea of a Triangle, which yet is none of the most abstract and comprehenfive ; for it must be neither Oblique, nor Restangular ; neither Equilateral, Isosceles, nor Scalenous ; but all, and none of these, at once. » -
« Now, let any Man look into his Thoughts, and try whether he has, or can attain to an Idea of a Triangle, correspondent to this Description. »

From the Notion of Abstract Ideas, Dr. Berkeley endeavours to shew, it was, that Bodies first came to be supposed to have an Existence of their own, out and independent of the Mind perceiving 'em. —
Can there be a greater Strain of Abstraction, says he, than to distinguish the Existence of sensible Objects from their being perceiv'd, so as to conceive them existing unperceiv'd. See BODY, and EXTERNAL World.

We shall only add, that abslracting, on the common System, is no more than generalizing : 'tis making one thing stand for an hundred, by omitting the Consideration of the Differences between 'em : It is taking several Differentsi. e. different Combinations, setting aside the Peculiarities in each, and considering only what is sound alike in all. —
Thus it is that I say, I love my Friend, love my Mistress, love my self, my Bottle, my Book, my Ease, &c.—
Not that it is possible I should have the same Sensation with respect to so many different sorts of things, things that stand in such different Relations to me ; but only that there appearing something in them all that bears a resemblance to the rest, in some Circumstances or other, I chuse to call 'em all by one Name, Love. For is I consider the Tendency of the Effects of them all, I shall find they lead me very different ways to very different Actions : and there is not more resemblance between the Causes than between the Effects : All the Analogy there is between them, is a sort of Pleasure or Satisfaction, arising upon the Application of the particular Object to its proper Organ, or Sense. -
The Abstract Idea of Love, then, will terminate in the Idea of Pleasure : But, 'tis certain, there can be no Idea of Pleasure, without a thing pleasant to excite it. Any other Abstract Idea of Pleasure, will amount to no more than a View or Perception of the Circumstances wherewith our Pleasures have been attended : But these are mere Externals, soreign to the pleasurable Sensation it self; which nothing but an Object applied in such and such a manner, can excite. —
To suppose an Idea of Pleasure produced obliquely, by any other than the proper Cause, is as absurd as to suppose an Idea of Sound, produced without a sonorous Object. The Mind has noPower of making any Ideas, call 'em what you will, whether Abstract, or Concrete ; or General, or Particular : Its Activity goes no farther than to the perceiving of such as are presemed to it : So that its Action is really no other than a degree of Passion. See SENSE.