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.
