y eye-socket.

The great result of speculation since the time of Kant is to teach us to
recognize that objects are essentially related to mind, and that the
principles which rule our thought enter, so to speak, into the
constitution of the things we know. A very slight acquaintance with the
history even of psychology, especially in modern times, shows that facts
are more and more retracted into thought. This science, which began with
a sufficiently common-sense view, not only of the reality and solidity
of the things of the outer world, but of their opposition to, or
independence of thought, is now thinning that world down into a mere
shadow--a something which excites sensation. It shows that external
things as we know them, and we are not concerned in any others, are, to
a very great extent, the product of our thinking activities. No one will
now subscribe to the Lockian or Humean view, of images impressed by
objects on mind: the object which "impresses" has first to be made by
mind, out of the results of nervous excitation. In a word, modern
psychology as well as modern metaphysics, is demonstrating more and more
fully the dependence of the world, as it is known, on the nature and
activity of man's mind. Every explanation of the world is found to be,
in this sense, idealistic; and in this respect, there is no difference
whatsoever between the interpretation given by science and that of
poetry, or religion, or philosophy. If we say that a thing is a
"substance," or has "a cause"; if, with the physicist, we assert the
principle of the transmutation of energy, or make use of the idea of
evolution with the biologist or geologist; nay, if we speak of time and
space with the mathematician, we use principles of unity derived from
self-consciousness, and interpret nature in terms of ourselves, just as
truly as the poet or philosopher, who makes love, or reason, the
constitutive element in things. If the practical man of the world
charges the poet and philosopher with living amidst phantoms, he can be
answered with a "_Tu quoque_." "How easy," said Emerson, "it is to show
the materialist that he also is a phantom walking and working amid
phantoms, and that he need only ask a question or two beyond his daily
questions to find his solid universe proving dim and impalpable before
his sense."

"Sense," which seems to show directly that the world is a solid reality,
not dependent in any way on thought, is found not to be reliable.