An Essay Concerning Humane Understanding, Volume 2: MDCXC, Based on the 2nd Edition, Books 3 and 4
John Locke · en
Our knowledge, as in other things, so in this, has so great a conformity
with our sight, that it is neither wholly necessary, nor wholly
voluntary. If our knowledge were altogether necessary, all men's
knowledge would not only be alike, but every man would know all that is
knowable; and if it were wholly voluntary, some men so little regard or
value it, that they would have extreme little, or none at all. Men that
have senses cannot choose but receive some ideas by them; and if they
have memory, they cannot but retain some of them; and if they have
any distinguishing faculty, cannot but perceive the agreement or
disagreement of some of them one with another; as he that has eyes, if
he will open them by day, cannot but see some objects, and perceive a
difference in them. But though a man with his eyes open in the light,
cannot but see, yet there be certain objects which he may choose whether
he will turn his eyes to; there may be in his reach a book containing
pictures and discourses, capable to delight or instruct him, which yet
he may never have the will to open, never take the pains to look into.
2. The application of our Faculties voluntary; but they being employed,
we know as things are, not as we please.
There is also another thing in a man's power, and that is, though he
turns his eyes sometimes towards an object, yet he may choose whether he
will curiously survey it, and with an intent application endeavour to
observe accurately all that is visible in it. But yet, what he does see,
he cannot see otherwise than he does. It depends not on his will to see
that black which appears yellow; nor to persuade himself, that what
actually scalds him, feels cold. The earth will not appear painted with
flowers, nor the fields covered with verdure, whenever he has a mind to
it: in the cold winter, he cannot help seeing it white and hoary, if he
will look abroad. Just thus is it with our understanding: all that is
voluntary in our knowledge is, the employing or withholding any of our
FACULTIES from this or that sort of objects, and a more or less accurate
survey of them: but, THEY BEING EMPLOYED, OUR WILL HATH NO POWER TO
DETERMINE THE KNOWLEDGE OF THE MIND ONE WAY OR ANOTHER; that is done
only by the objects themselves, as far as they are clearly discovered.
And therefore, as far as men's senses are conversant about external
objects, the mind cannot but receive those ideas which are presented by
them, and be informed of the existence of things without: and so far as
men's thoughts converse with their own determined ideas, they cannot
but in some measure observe the agreement or disagreement that is to be
found amongst some of them, which is so far knowledge: and if they have
names for those ideas which they have thus considered, they must needs
be assured of the truth of those propositions which express that
agreement or disagreement they perceive in them, and be undoubtedly
convinced of those truths. For what a man sees, he cannot but see; and