ce of matter, reduced, if they would be
consistent in their reasonings, to deny, each man for himself, that he
has any proper evidence of the existence of other minds than his own?

He denies, while he has the sensation of colour, that there exists
colour out of himself, unless in thinking and percipient beings
constituted in a manner similar to that in which he is constituted. And
the same of the sensations of hot and cold, sweet and bitter, and
odours offensive or otherwise. He affirms, while he has the sensation of
length, breadth and thickness, that there is no continuous substance out
of himself, possessing the attributes of length, breadth and thickness
in any way similar to the sensation of which he is conscious.
He professes therefore that he has no evidence, arising from his
observation of what we call matter, of the actual existence of a
material world. He looks into himself, and all he finds is sensation;
but sensation cannot be a property of inert matter. There is therefore
no assignable analogy between the causes of his sensations, whatever
they may be, and the sensations themselves; and the material world, such
as we apprehend it, is the mere creature of his own mind.

Let us next consider how this question stands as to the conceptions he
entertains respecting the minds of other men. That which gives him the
sensation of colour, is not any thing coloured out of himself; and that
which gives him the sensation of length, breadth and thickness, is
not any thing long, broad and thick in a manner corresponding with the
impression he receives. There is nothing in the nature of a parallel, a
type and its archetype, between that which is without him and that which
is within, the impresser and the impression. This is the point supposed
to be established by Locke and Newton, and by those who have followed
the reasonings of these philosophers into their remotest consequences.

But the case is far otherwise in the impressions we receive respecting
the minds of other men. In colour it has been proved by these authors
that there is no express correspondence and analogy between the cause of
the sensation and the sensation. They are not part and counterpart.
But in mind there is a precise resemblance and analogy between the
conceptions we are led to entertain respecting other men, and what
we know of ourselves. I and my associate, or fellow-man, are like two
instruments of music constructed upon the same model. We have e