Philosiphy

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Human Understanding

Chapter IX Of Perception

1. Perception the first simple idea of reflection. Percep-

tion, as it is the first faculty of the mind exercised about

our ideas; so it is the first and simplest idea we have

from reflection, and is by some called thinking in gen-

eral. Though thinking, in the propriety of the English

tongue, signifies that sort of operation in the mind about

its ideas, wherein the mind is active; where it, with

some degree of voluntary attention, considers anything.

For in bare naked perception, the mind is, for the most

part, only passive; and what it perceives, it cannot avoid

perceiving.

2. Reflection alone can give us the idea of what percep-

tion is. What perception is, every one will know better by

reflecting on what he does himself, when he sees, hears,

feels, &c., or thinks, than by any discourse of mine. Who-

ever reflects on what passes in his own mind cannot miss

it. And if he does not reflect, all the words in the world

cannot make him have any notion of it.

3. Arises in sensation only when the mind notices the

organic impression. This is certain, that whatever alter-

ations are made in the body, if they reach not the mind;

whatever impressions are made on the outward parts, if

they are not taken notice of within, there is no percep-

tion. Fire may burn our bodies with no other effect than it

does a billet, unless the motion be continued to the brain,

and there the sense of heat, or idea of pain, be produced in

the mind; wherein consists actual perception.

4. Impulse on the organ insufficient. How often may a

man observe in himself, that whilst his mind is intently

employed in the contemplation of some objects, and

curiously surveying some ideas that are there, it takes

no notice of impressions of sounding bodies made upon

the organ of hearing, with the same alteration that uses

to be for the producing the idea of sound? A sufficient

impulse there may be on the organ; but it not reaching

the observation of the mind, there follows no percep-

tion: and though the motion that uses to produce the

idea of sound be made in the ear, yet no sound is heard.

Want of sensation, in this case, is not through any de-

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fect in the organ, or that the man’s ears are less af-

fected than at other times when he does hear: but that

which uses to produce the idea, though conveyed in by

the usual organ, not being taken notice of in the un-

derstanding, and so imprinting no idea in the mind,

there follows no sensation. So that wherever there is

sense or perception, there some idea is actually pro-

duced, and present in the understanding.

5. Children, though they may have ideas in the womb,

have none innate. Therefore I doubt not but children,

by the exercise of their senses about objects that affect

them in the womb, receive some few ideas before they

are born, as the unavoidable effects, either of the bod-

ies that environ them, or else of those wants or diseases

they suffer; amongst which (if one may conjecture con-

cerning things not very capable of examination) I think

the ideas of hunger and warmth are two: which prob-

ably are some of the first that children have, and which

they scarce ever part with again.

6. The effects of sensation in the womb. But though it

be reasonable to imagine that children receive some ideas

before they come into the world, yet these simple ideas

are far from those innate principles which some con-

tend for, and we, above, have rejected. These here men-

tioned, being the effects of sensation, are only from

some affections of the body, which happen to them there,

and so depend on something exterior to the mind; no

otherwise differing in their manner of production from

other ideas derived from sense, but only in the prece-

dency of time. Whereas those innate principles are sup-

posed to be quite of another nature; not coming into

the mind by any accidental alterations in, or operations

on the body; but, as it were, original characters im-

pressed upon it, in the very first moment of its being

and constitution.

7. Which ideas appear first, is not evident, nor impor-

tant. As there are some ideas which we may reasonably

suppose may be introduced into the minds of children

in the womb, subservient to the necessities of their life

and being there: so, after they are born, those ideas are

the earliest imprinted which happen to be the sensible

qualities which first occur to them; amongst which light

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is not the least considerable, nor of the weakest effi-

cacy. And how covetous the mind is to be furnished

with all such ideas as have no pain accompanying them,

may be a little guessed by what is observable in children

new-born; who always turn their eyes to that part from

whence the light comes, lay them how you please. But

the ideas that are most familiar at first, being various

according to the divers circumstances of children’s first

entertainment in the world, the order wherein the sev-

eral ideas come at first into the mind is very various,

and uncertain also; neither is it much material to know

it.

8. Sensations often changed by the judgment. We are

further to consider concerning perception, that the ideas

we receive by sensation are often, in grown people, al-

tered by the judgment, without our taking notice of it.

When we set before our eyes a round globe of any uni-

form colour, v.g. gold, alabaster, or jet, it is certain that

the idea thereby imprinted on our mind is of a flat circle,

variously shadowed, with several degrees of light and

brightness coming to our eyes. But we having, by use,

been accustomed to perceive what kind of appearance

convex bodies are wont to make in us; what alterations

are made in the reflections of light by the difference of

the sensible figures of bodies;—the judgment presently,

by an habitual custom, alters the appearances into their

causes. So that from that which is truly variety of shadow

or colour, collecting the figure, it makes it pass for a

mark of figure, and frames to itself the perception of a

convex figure and an uniform colour; when the idea we

receive from thence is only a plane variously coloured,

as is evident in painting. To which purpose I shall here

insert a problem of that very ingenious and studious

promoter of real knowledge, the learned and worthy Mr.

Molyneux, which he was pleased to send me in a letter

some months since; and it is this:—”Suppose a man

born blind, and now adult, and taught by his touch to

distinguish between a cube and a sphere of the same

metal, and nighly of the same bigness, so as to tell,

when he felt one and the other, which is the cube,

which the sphere. Suppose then the cube and sphere

placed on a table, and the blind man be made to see:

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quaere, whether by his sight, before he touched them,

he could now distinguish and tell which is the globe,

which the cube?” To which the acute and judicious

proposer answers, “Not. For, though he has obtained

the experience of how a globe, how a cube affects his

touch, yet he has not yet obtained the experience, that

what affects his touch so or so, must affect his sight so

or so; or that a protuberant angle in the cube, that

pressed his hand unequally, shall appear to his eye as it

does in the cube.”—I agree with this thinking gentle-

man, whom I am proud to call my friend, in his answer

to this problem; and am of opinion that the blind man,

at first sight, would not be able with certainty to say

which was the globe, which the cube, whilst he only

saw them; though he could unerringly name them by

his touch, and certainly distinguish them by the differ-

ence of their figures felt. This I have set down, and

leave with my reader, as an occasion for him to consider

how much he may be beholden to experience, improve-

ment, and acquired notions, where he thinks he had

not the least use of, or help from them. And the rather,

because this observing gentleman further adds, that

“having, upon the occasion of my book, proposed this

to divers very ingenious men, he hardly ever met with

one that at first gave the answer to it which he thinks

true, till by hearing his reasons they were convinced.”

9. This judgment apt to be mistaken for direct percep-

tion. But this is not, I think, usual in any of our ideas,

but those received by sight. Because sight, the most

comprehensive of all our senses, conveying to our minds

the ideas of light and colours, which are peculiar only

to that sense; and also the far different ideas of space,

figure, and motion, the several varieties whereof change

the appearances of its proper object, viz. light and

colours; we bring ourselves by use to judge of the one

by the other. This, in many cases by a settled habit,—in

things whereof we have frequent experience, is performed

so constantly and so quick, that we take that for the

perception of our sensation which is an idea formed by

our judgment; so that one, viz. that of sensation, serves

only to excite the other, and is scarce taken notice of

itself;—as a man who reads or hears with attention and

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understanding, takes little notice of the characters or

sounds, but of the ideas that are excited in him by them.

10. How, by habit, ideas of sensation are unconsciously

changed into ideas of judgment. Nor need we wonder

that this is done with so little notice, if we consider

how quick the actions of the mind are performed. For,

as itself is thought to take up no space, to have no

extension; so its actions seem to require no time, but

many of them seem to be crowded into an instant. I

speak this in comparison to the actions of the body.

Any one may easily observe this in his own thoughts,

who will take the pains to reflect on them. How, as it

were in an instant, do our minds, with one glance, see

all the parts of a demonstration, which may very well be

called a long one, if we consider the time it will require

to put it into words, and step by step show it another?

Secondly, we shall not be so much surprised that this is

done in us with so little notice, if we consider how the

facility which we get of doing things, by a custom of

doing, makes them often pass in us without our notice.

Habits, especially such as are begun very early, come at

last to produce actions in us, which often escape our

observation. How frequently do we, in a day, cover our

eyes with our eyelids, without perceiving that we are at

all in the dark! Men that, by custom, have got the use

of a by-word, do almost in every sentence pronounce

sounds which, though taken notice of by others, they

themselves neither hear nor observe. And therefore it is

not so strange, that our mind should often change the

idea of its sensation into that of its judgment, and make

one serve only to excite the other, without our taking

notice of it.

11. Perception puts the difference between animals and

vegetables. This faculty of perception seems to me to be,

that which puts the distinction betwixt the animal king-

dom and the inferior parts of nature. For, however veg-

etables have, many of them, some degrees of motion,

and upon the different application of other bodies to

them, do very briskly alter their figures and motions,

and so have obtained the name of sensitive plants, from

a motion which has some resemblance to that which in

animals follows upon sensation: yet I suppose it is all

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bare mechanism; and no otherwise produced than the

turning of a wild oat-beard, by the insinuation of the

particles of moisture, or the shortening of a rope, by

the affusion of water. All which is done without any

sensation in the subject, or the having or receiving any

ideas.

12. Perception in all animals. Perception, I believe, is,

in some degree, in all sorts of animals; though in some

possibly the avenues provided by nature for the recep-

tion of sensations are so few, and the perception they

are received with so obscure and dull, that it comes

extremely short of the quickness and variety of sensa-

tion which is in other animals; but yet it is sufficient

for, and wisely adapted to, the state and condition of

that sort of animals who are thus made. So that the

wisdom and goodness of the Maker plainly appear in all

the parts of this stupendous fabric, and all the several

degrees and ranks of creatures in it.

13. According to their condition. We may, I think, from

the make of an oyster or cockle, reasonably conclude

that it has not so many, nor so quick senses as a man,

or several other animals; nor if it had, would it, in that

state and incapacity of transferring itself from one place

to another, be bettered by them. What good would sight

and hearing do to a creature that cannot move itself to

or from the objects wherein at a distance it perceives

good or evil? And would not quickness of sensation be

an inconvenience to an animal that must lie still where

chance has once placed it, and there receive the afflux

of colder or warmer, clean or foul water, as it happens to

come to it?

14. Decay of perception in old age. But yet I cannot

but think there is some small dull perception, whereby

they are distinguished from perfect insensibility. And

that this may be so, we have plain instances, even in

mankind itself. Take one in whom decrepit old age has

blotted out the memory of his past knowledge, and clearly

wiped out the ideas his mind was formerly stored with,

and has, by destroying his sight, hearing, and smell quite,

and his taste to a great degree, stopped up almost all

the passages for new ones to enter; or if there be some

of the inlets yet half open, the impressions made are

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scarcely perceived, or not at all retained. How

far such an one (notwithstanding all that is boasted of

innate principles) is in his knowledge and intellectual

faculties above the condition of a cockle or an oyster, I

leave to be considered. And if a man had passed sixty

years in such a state, as it is possible he might, as well

as three days, I wonder what difference there would be,

in any intellectual perfections, between him and the

lowest degree of animals.

15. Perception the inlet of all materials of knowledge.

Perception then being the first step and degree towards

knowledge, and the inlet of all the materials of it; the

fewer senses any man, as well as any other creature,

hath; and the fewer and duller the impressions are that

are made by them, and the duller the faculties are that

are employed about them,—the more remote are they

from that knowledge which is to be found in some men.

But this being in great variety of degrees (as may be

perceived amongst men) cannot certainly be discovered

in the several species of animals, much less in their par-

ticular individuals. It suffices me only to have remarked

here,—that perception is the first operation of all our

intellectual faculties, and the inlet of all knowledge in

our minds. And I am apt too to imagine, that it is per-

ception, in the lowest degree of it, which puts the bound-

aries between animals and the inferior ranks of crea-

tures. But this I mention only as my conjecture by the

by; it being indifferent to the matter in hand which way

the learned shall determine of it.

Chapter X Of Retention

1. Contemplation. The next faculty of the mind, whereby

it makes a further progress towards knowledge, is that

which I call retention; or the keeping of those simple

ideas which from sensation or reflection it hath received.

This is done two ways.

First, by keeping the idea which is brought into it, for

some time actually in view, which is called contemplation.

2. Memory. The other way of retention is, the power to

revive again in our minds those ideas which, after im-