A Treatise Concerning the Principles of Human Knowledge by George Berkeley. - HTML preview

PLEASE NOTE: This is an HTML preview only and some elements such as links or page numbers may be incorrect.
Download the book in PDF, ePub, Kindle for a complete version.

INTRODUCTION

1. Philosophy being nothing else but THE STUDY OF WISDOM

AND TRUTH, it

may with reason be expected that those who have spent most time and pains

in it should enjoy a greater calm and serenity of mind, a greater

clearness and evidence of knowledge, and be less disturbed with doubts

and difficulties than other men. Yet so it is, we see the illiterate bulk

of mankind that walk the high-road of plain common sense, and are

governed by the dictates of nature, for the most part easy and

undisturbed. To them nothing THAT IS FAMILIAR appears unaccountable or

difficult to comprehend. They complain not of any want of evidence in

their senses, and are out of all danger of becoming SCEPTICS. But no

sooner do we depart from sense and instinct to follow the light of a

superior principle, to reason, meditate, and reflect on the nature of

things, but a thousand scruples spring up in our minds concerning those

things which before we seemed fully to comprehend.

Prejudices and errors

of sense do from all parts discover themselves to our view; and,

endeavouring to correct these by reason, we are insensibly drawn into

uncouth paradoxes, difficulties, and inconsistencies, which multiply and

grow upon us as we advance in speculation, till at length, having

wandered through many intricate mazes, we find ourselves just where we

were, or, which is worse, sit down in a forlorn Scepticism.

2. The cause of this is thought to be the obscurity of things, or the

natural weakness and imperfection of our understandings.

It is said, the

faculties we have are few, and those designed by nature for the SUPPORT

and comfort of life, and not to penetrate into the INWARD ESSENCE and

constitution of things. Besides, the mind of man being finite, when it

treats of things which partake of infinity, it is not to be wondered at

if it run into absurdities and contradictions, out of which it is

impossible it should ever extricate itself, it being of the nature of

infinite not to be comprehended by that which is finite.

3. But, perhaps, we may be too partial to ourselves in placing the fault

originally in our faculties, and not rather in the wrong use we make of

them. IT IS A HARD THING TO SUPPOSE THAT RIGHT

DEDUCTIONS FROM TRUE

PRINCIPLES SHOULD EVER END IN CONSEQUENCES WHICH CANNOT

BE MAINTAINED or

made consistent. We should believe that God has dealt more bountifully

with the sons of men than to give them a strong desire for that knowledge

which he had placed quite out of their reach. This were not agreeable to

the wonted indulgent methods of Providence, which, whatever appetites it

may have implanted in the creatures, doth usually furnish them with such

means as, if rightly made use of, will not fail to satisfy them. Upon the

whole, I am inclined to think that the far greater part, if not all, of

those difficulties which have hitherto amused philosophers, and blocked

up the way to knowledge, are entirely owing to ourselves--that we have

first raised a dust and then complain we cannot see.

4. My purpose therefore is, to try if I can discover what those

Principles are which have introduced all that doubtfulness and

uncertainty, those absurdities and contradictions, into the several sects

of philosophy; insomuch that the wisest men have thought our ignorance

incurable, conceiving it to arise from the natural dulness and limitation

of our faculties. And surely it is a work well deserving our pains to

make a strict inquiry concerning the First Principles of Human Knowledge,

to sift and examine them on all sides, especially since there may be some

grounds to suspect that those lets and difficulties, which stay and

embarrass the mind in its search after truth, do not spring from any

darkness and intricacy in the objects, or natural defect in the

understanding, so much as from false Principles which have been insisted

on, and might have been avoided.

5. How difficult and discouraging soever this attempt may seem, when I

consider how many great and extraordinary men have gone before me in the

like designs, yet I am not without some hopes--upon the consideration

that the largest views are not always the clearest, and that he who is

short--sighted will be obliged to draw the object nearer, and may,

perhaps, by a close and narrow survey, discern that which had escaped far

better eyes.

6. A CHIEF SOURCE OF ERROR IN ALL PARTS OF KNOWLEDGE.--

In order to

prepare the mind of the reader for the easier conceiving what

follows, it is proper to premise somewhat, by way of Introduction,

concerning the nature and abuse of Language. But the unravelling this

matter leads me in some measure to anticipate my design, by taking notice

of what seems to have had a chief part in rendering speculation intricate

and perplexed, and to have occasioned innumerable errors and difficulties

in almost all parts of knowledge. And that is the opinion that the mind

has a power of framing ABSTRACT IDEAS or notions of things. He who is

not a perfect stranger to the writings and disputes of philosophers must

needs acknowledge that no small part of them are spent about abstract

ideas. These are in a more especial manner thought to be the object of

those sciences which go by the name of LOGIC and METAPHYSICS, and of all

that which passes under the notion of the most abstracted and sublime

learning, in all which one shall scarce find any question handled in such

a manner as does not suppose their existence in the mind, and that it is

well acquainted with them.

7. PROPER ACCEPTATION OF ABSTRACTION.--It is agreed on all hands that the

qualities or modes of things do never REALLY EXIST EACH

OF THEM APART BY

ITSELF, and separated from all others, but are mixed, as it were, and

blended together, several in the same object. But, we are told, the mind

being able to consider each quality singly, or abstracted from those other

qualities with which it is united, does by that means frame to itself

abstract ideas. For example, there is perceived by sight an object

extended, coloured, and moved: this mixed or compound idea the mind

resolving into its simple, constituent parts, and viewing each by itself,

exclusive of the rest, does frame the abstract ideas of extension, colour,

and motion. Not that it is possible for colour or motion to exist without

extension; but only that the mind can frame to itself by ABSTRACTION the

idea of colour exclusive of extension, and of motion exclusive of both

colour and extension.

8. OF GENERALIZING [Note].--Again, the mind having observed 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 considers apart or

singles out by itself that which is common, making thereof a most abstract

idea of extension, which is neither line, surface, nor solid, nor has any

figure or magnitude, but is an idea entirely prescinded from all these. So

likewise the mind, by leaving out of the particular colours perceived by

sense that which distinguishes them one from another, and retaining that

only which is COMMON TO ALL, makes an idea of colour in abstract which is

neither red, nor blue, nor white, nor any other determinate colour. And,

in like manner, by considering motion abstractedly not only from the body

moved, but likewise from the figure it describes, and all particular

directions and velocities, the abstract idea of motion is framed; which

equally corresponds to all particular motions whatsoever that may be

perceived by sense.

[Note: Vide Reid, on the Intellectual Powers of Man, Essay V,

chap iii. sec. 1, edit. 1843]

9. OF COMPOUNDING.--And as the mind frames to itself abstract ideas of

qualities or MODES, so does it, by the same precision or mental

separation, attain abstract ideas of the more compounded BEINGS

which include several coexistent qualities. For example, the mind

having observed that Peter, James, and John resemble each other

in certain common agreements of shape and other qualities, leaves

out of the complex or compounded idea it has of Peter, James, and

any other particular man, that which is peculiar to each, retaining

only what is common to all, and so makes an abstract idea wherein

all the particulars equally partake--abstracting entirely from

and cutting off all those circumstances and differences which might

determine it to any particular existence. And after this manner it is

said we come by the abstract idea of MAN, or, if you please, humanity, or

human nature; wherein it is true there is included colour, because there

is no man but has some colour, but then it can be neither white, nor

black, nor any particular colour, because there is no one particular

colour wherein all men partake. So likewise there is included stature,

but then it is neither tall stature, nor low stature, nor yet middle

stature, but something abstracted from all these. And so of the rest.

Moreover, their being a great variety of other creatures that 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 the living creatures, frames the idea of ANIMAL, which

abstracts not only from all particular men, but also all birds, beasts,

fishes, and insects. The constituent parts of the 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 shape or

figure common to all animals, without covering, either of hair, or

feathers, or scales, &c., nor yet naked: hair, feathers, scales, and

nakedness being the distinguishing properties of particular animals, and

for that reason left out of 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[Note.].

[Note: Vide Hobbes' Tripos, ch. v. sect. 6.]

10. TWO OBJECTIONS TO THE EXISTENCE OF ABSTRACT IDEAS.--

Whether

others have this wonderful faculty of ABSTRACTING THEIR

IDEAS,

they best can tell: for myself, I find indeed I have a faculty of

imagining, or representing to myself, the ideas of those particular

things I have perceived, and of variously compounding and dividing them.

I can imagine a man with two heads, or the upper parts of a man joined to

the body of a horse. I can consider the hand, the eye, the nose, each by

itself abstracted or separated from the rest of the body. But then

whatever hand or eye I imagine, it must have some particular shape and

colour. Likewise the idea of man that I frame to myself must be either of

a white, or a black, or a tawny, a straight, or a crooked, a tall, or a

low, or a middle-sized man. I cannot by any effort 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 whatsoever.

To be plain, I

own myself able to abstract IN ONE SENSE, as when I consider some

particular parts or qualities separated from others, with which, though

they are united in some object, yet it is possible they may really exist

without them. But I deny that I can abstract from one another, or

conceive separately, those qualities which it is impossible should exist

so separated; or that I can frame a general notion, by abstracting from

particulars in the manner aforesaid--which last are the two proper

acceptations of ABSTRACTION. And there are grounds to think most men will

acknowledge themselves to be in my case. The generality of men which are

simple and illiterate never pretend to ABSTRACT NOTIONS.

It is said

they are difficult and not to be attained without pains and study; we may

therefore reasonably conclude that, if such there be, they are confined

only to the learned.

11. I proceed to examine what can be alleged in DEFENCE

OF THE DOCTRINE

OF ABSTRACTION, and try if I can discover what it is that inclines the

men of speculation to embrace an opinion so remote from common sense as

that seems to be. There has been a late deservedly esteemed philosopher

who, no doubt, has given it very much countenance, by seeming to think

the having abstract general ideas is what puts the widest difference in

point of understanding betwixt man and beast. "The having of general

ideas," saith he, "is that which puts a perfect distinction betwixt man

and brutes, and is an excellency which the faculties of brutes do by no

means attain unto. For, it is evident we observe no foot-steps in them of

making use of general signs for universal ideas; from which we have

reason to imagine that they have not the FACULTY OF

ABSTRACTING, or

making general ideas, since they have no use of words or any other

general signs." And a little after: "Therefore, I think, we may suppose

that it is in this that the species of brutes are discriminated from men,

and it is that proper difference wherein they are wholly separated, and

which at last widens to so wide a distance. For, if they have any ideas

at all, and are not bare machines (as some would have them), we cannot

deny them to have some reason. It seems as evident to me that they do,

some of them, in certain instances reason as that they have sense; but it

is only in particular ideas, just as they receive them from their senses.

They are the best of them tied up within those narrow bounds, and have

not (as I think) the faculty to enlarge them by any kind of

ABSTRACTION." Essay on Human Understanding, II. xi. 10

and 11. I readily

agree with this learned author, that the faculties of brutes can by no

means attain to ABSTRACTION. But then if this be made the distinguishing

property of that sort of animals, I fear a great many of those that pass

for men must be reckoned into their number. The reason that is here

assigned why we have no grounds to think brutes have abstract general

ideas is, that we observe in them no use of words or any other general

signs; which is built on this supposition--that the making use of words

implies the having general ideas. From which it follows that men who use

language are able to ABSTRACT or GENERALIZE their ideas.

That this is the

sense and arguing of the author will further appear by his answering the

question he in another place puts: "Since all things that exist are only

particulars, how come we by general terms?" His answer is: "Words become

general by being made the signs of general ideas."--

Essay on Human

Understanding, IV. iii. 6. But [Note. 1] it seems that a word becomes

general by being made the sign, not of an ABSTRACT

general idea, but of

several particular ideas [Note. 2], any one of which it indifferently

suggests to the mind. For example, when it is said "the change of motion

is proportional to the impressed force," or that

"whatever has extension

is divisible," these propositions are to be understood of motion

and extension in general; and nevertheless it will not follow that

they suggest to my thoughts an idea of motion without a body moved,

or any determinate direction and velocity, or that I must conceive

an abstract general idea of extension, which is neither line, surface,

nor solid, neither great nor small, black, white, nor red, nor of any

other determinate colour. It is only implied that whatever particular

motion I consider, whether it be swift or slow, perpendicular,

horizontal, or oblique, or in whatever object, the axiom concerning

it holds equally true. As does the other of every particular extension,

it matters not whether line, surface, or solid, whether of this or

that magnitude or figure.

[Note 1: "TO THIS I CANNOT ASSENT, BEING OF OPINION,"

edit of 1710.]

[Note 2: Of the same sort.]

12. EXISTENCE OF GENERAL IDEAS ADMITTED.--By observing how ideas

become general we may the better judge how words are made so.

And here it is to be noted that I do not deny absolutely there

are general ideas, but only that there are any ABSTRACT

GENERAL

IDEAS; for, in the passages we have quoted wherein there is

mention of general ideas, it is always supposed that they are formed by

ABSTRACTION, after the manner set forth in sections 8

and 9. Now, if we

will annex a meaning to our words, and speak only of what we can

conceive, I believe we shall acknowledge that an idea which, considered

in itself, is particular, becomes general by being made to represent or

stand for all other particular ideas of the SAME SORT.

To make this plain

by an example, suppose a geometrician is demonstrating the method of

cutting a line in two equal parts. He draws, for instance, a black line

of an inch in length: this, which in itself is a particular line, is

nevertheless with regard to its signification general, since, as it is

there used, it represents all particular lines whatsoever; so that what

is demonstrated of it is demonstrated of all lines, or, in other words,

of a line in general. And, as that particular line becomes general by

being made a sign, so the name LINE, which taken absolutely is

PARTICULAR, by being a sign is made GENERAL. And as the former owes its

generality not to its being the sign of an abstract or general line, but

of ALL PARTICULAR right lines that may possibly exist, so the latter must

be thought to derive its generality from the same cause, namely, the

VARIOUS PARTICULAR lines which it indifferently denotes.

[Note.]

[Note: "I look upon this (doctrine) to be one of the greatest and most

valuable discoveries that have been made of late years in the republic

of letters."--Treatise of Human Nature, book i, part i, sect. 7. Also

Stewart's Philosophy of the Mind, part i, chapt. iv.

sect. iii. p. 99.]

13. ABSTRACT GENERAL IDEAS NECESSARY, ACCORDING TO

LOCKE.--To give

the reader a yet clearer view of the nature of abstract ideas,

and the uses they are thought necessary to, I shall add one more

passage out of the Essay on Human Understanding, (IV.

vii. 9) which is as

follows: "ABSTRACT IDEAS are not so obvious or easy to children or the

yet unexercised mind as particular ones. If they seem so to grown men it

is only because by constant and familiar use they are made so. For, when

we nicely reflect upon them, we shall find that general ideas are

fictions and contrivances of the mind, that carry difficulty with them,

and do not so easily offer themselves as we are apt to imagine. For

example, does it not require some pains and skill to form the general

idea of a triangle (which is yet none of the most abstract,

comprehensive, and difficult); for it must be neither oblique nor

rectangle, neither equilateral, equicrural, nor scalenon, but ALL AND

NONE of these at once? In effect, it is something imperfect that cannot

exist, an idea wherein some parts of several different and INCONSISTENT

ideas are put together. It is true the mind in this imperfect state has

need of such ideas, and makes all the haste to them it can, for the

CONVENIENCY OF COMMUNICATION AND ENLARGEMENT OF

KNOWLEDGE, to both which

it is naturally very much inclined. But yet one has reason to suspect

such ideas are marks of our imperfection. At least this is enough to show

that the most abstract and general ideas are not those that the mind is

first and most easily acquainted with, nor such as its earliest knowledge

is conversant about."--If any man has the faculty of framing in his mind

such an idea of a triangle as is here described, it is in vain to pretend

to dispute him out of it, nor would I go about it. All I desire is that

the reader would fully and certainly inform himself whether he has such

an idea or no. And this, methinks, can be no hard task for anyone to

perform. What more easy than for anyone to look a little into his own

thoughts, and there try whether he has, or can attain to have, an idea

that shall correspond with the description that is here given of the

general idea of a triangle, which is NEITHER OBLIQUE NOR

RECTANGLE,

EQUILATERAL, EQUICRURAL NOR SCALENON, BUT ALL AND NONE

OF THESE AT ONCE?

14. BUT THEY ARE NOT NECESSARY FOR COMMUNICATION.--Much is here

said of the difficulty that abstract ideas carry with them, and

the pains and skill requisite to the forming them. And it is on

all hands agreed that there is need of great toil and labour of the mind,

to emancipate our thoughts from particular objects, and raise them to

those sublime speculations that are conversant about abstract ideas. From

all which the natural consequence should seem to be, that so DIFFICULT a

thing as the forming abstract ideas was not necessary for COMMUNICATION,

which is so EASY and familiar to ALL SORTS OF MEN. But, we are told, if

they seem obvious and easy to grown men, IT IS ONLY

BECAUSE BY CONSTANT

AND FAMILIAR USE THEY ARE MADE SO. Now, I would fain know at what time it

is men are employed in surmounting that difficulty, and furnishing

themselves with those necessary helps for discourse. It cannot be when

they are grown up, for then it seems they are not conscious of any such

painstaking; it remains therefore to be the business of their childhood.

And surely the great and multiplied labour of framing abstract notions

will be found a hard task for that tender age. Is it not a hard thing to

imagine that a couple of children cannot prate together of their

sugar-plums and rattles and the rest of their little trinkets, till they

have first tacked together numberless inconsistencies, and so framed in

their minds ABSTRACT GENERAL IDEAS, and annexed them to every common name

they make use of?

15. NOR FOR THE ENLARGEMENT OF KNOWLEDGE.--Nor do I think them

a whit more needful for the ENLARGEMENT OF KNOWLEDGE

than for

COMMUNICATION. It is, I know, a point much insisted on, that

all knowledge and demonstration are about universal notions, to

which I fully agree: but then it doth not appear to me that those notions

are formed by ABSTRACTION in the manner PREMISED--

UNIVERSALITY, so far as

I can comprehend, not consisting in the absolute, POSITIVE nature or

conception of anything, but in the RELATION it bears to the particulars

signified or represented by it; by virtue whereof it is that things,

names, or notions, being in their own nature PARTICULAR, are rendered

UNIVERSAL. Thus, when I demonstrate any proposition concerning triangles,

it is to be supposed that I have in view the universal idea of a

triangle; which ought not to be understood as if I could frame an idea of

a triangle which was neither equilateral, nor scalenon, nor equicrural;

but only that the particular triangle I consider, whether of this or that

sort it matters not, doth equally stand for and represent all rectilinear

triangles whatsoever, and is in that sense UNIVERSAL.

All which seems

very plain and not to include any difficulty in it.

16. OBJECTION.--ANSWER.--But here it will be dem