A System of Logic: Ratiocinative and Inductive, 7th Edition, Vol. I
John Stuart Mill · en
§ 8. Body having now been defined the external cause, and (according to
the more reasonable opinion) the unknown external cause, to which we
refer our sensations; it remains to frame a definition of Mind. Nor,
after the preceding observations, will this be difficult. For, as our
conception of a body is that of an unknown exciting cause of sensations,
so our conception of a mind is that of an unknown recipient, or
percipient, of them; and not of them alone, but of all our other
feelings. As body is understood to be the mysterious something which
excites the mind to feel, so mind is the mysterious something which
feels and thinks. It is unnecessary to give in the case of mind, as we
gave in the case of matter, a particular statement of the sceptical
system by which its existence as a Thing in itself, distinct from the
series of what are denominated its states, is called in question. But it
is necessary to remark, that on the inmost nature (whatever be meant by
inmost nature) of the thinking principle, as well as on the inmost
nature of matter, we are, and with our faculties must always remain,
entirely in the dark. All which we are aware of, even in our own minds,
is (in the words of Mr. James Mill) a certain "thread of consciousness;"
a series of feelings, that is, of sensations, thoughts, emotions, and
volitions, more or less numerous and complicated. There is a something I
call Myself, or, by another form of expression, my mind, which I
consider as distinct from these sensations, thoughts, &c.; a something
which I conceive to be not the thoughts, but the being that has the
thoughts, and which I can conceive as existing for ever in a state of
quiescence, without any thoughts at all. But what this being is, though
it is myself, I have no knowledge, other than the series of its states
of consciousness. As bodies manifest themselves to me only through the
sensations of which I regard them as the causes, so the thinking
principle, or mind, in my own nature, makes itself known to me only by
the feelings of which it is conscious. I know nothing about myself, save
my capacities of feeling or being conscious (including, of course,
thinking and willing): and were I to learn anything new concerning my
own nature, I cannot with my present faculties conceive this new
information to be anything else, than that I have some additional
capacities, as yet unknown to me, of feeling, thinking, or willing.