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 what he perceives, he cannot but know that he
perceives.
3. Instance in numbers.
Thus he that has got the ideas of numbers,
and hath taken the pains to compare one, two, and three, to six,
cannot choose but know that they are equal: he that hath got the
idea of a triangle, and found the ways to measure its angles and their
magnitudes, is certain that its three angles are equal to two right
ones; and can as little doubt of that, as of this truth, that it is
impossible for the same thing to be, and not to be.
4. Instance in natural religion.
He also that hath the idea of an
intelligent, but frail and weak being, made by and depending on
another, who is eternal, omnipotent, perfectly wise and good, will
as certainly know that man is to honour, fear, and obey God, as that
the sun shines when he sees it. For if he hath but the ideas of two
such beings in his mind, and will turn his thoughts that way, and
consider them, he will as certainly find that the inferior, finite,
and dependent is under an obligation to obey the supreme and infinite,
as he is certain to find that three, four, and seven are less than
fifteen; if he will consider and compute those numbers: nor can he
be surer in a clear morning that the sun is risen; if he will but open
his eyes and turn them that way. But yet these truths, being ever so
certain, ever so clear, he may be ignorant of either, or all of
them, who will never take the pains to employ his faculties, as he
should, to inform himself about them.