hout sensation, much more are they without intelligence. May I ask
you, then, to try your hand upon this problem? Take your dead
hydrogen atoms, your dead oxygen atoms, your dead carbon atoms, your
dead nitrogen atoms, your dead phosphorus atoms, and all the other
atoms, dead as grains of shot, of which the brain is formed. Imagine
them separate and sensationless; observe them running together and
forming all imaginable combinations. This, as a purely mechanical
process, is seeable by the mind. But can you see, or dream, or in any
way imagine, how out of that mechanical act, and from these
individually dead atoms, sensation, thought, and emotion are to rise?
Are you likely to extract Homer out of the rattling of dice, or the
Differential Calculus out of the clash of billiard balls? ... I can
follow a particle of musk until it reaches the olfactory nerve; I can
follow the waves of sound until their tremors reach the water of the
labyrinth, and set the otoliths and Corti's fibres in motion; I can
also visualise the waves of aether as they cross the eye and hit the
retina. Nay, more, I am able to pursue to the central organ the
motion thus imparted at the periphery, and to see in idea the very
molecules of the brain thrown into tremors. My insight is not baffled
by these physical processes. What baffles and bewilders me is the
notion that from these physical tremors things so utterly incongruous
with them as sensation, thought, and emotion can be derived.' It is
only a complete misapprehension of our true relationship that could
induce Mr. Martineau to represent Du Bois-Reymond and myself as
opposed to each other.

'The affluence of illustration,' writes an able and sympathetic
reviewer of this essay, in the 'New York Tribune,' 'in which Mr.
Martineau delights often impairs the distinctness of his statements by
diverting the attention of the reader from the essential points of his
discussion to the beauty of his imagery, and thus diminishes their
power of conviction. 'To the beauties here referred to I bear willing
testimony; but the reviewer is strictly just in his estimate of their
effect upon my critic's logic. The 'affluence of illustration,' and
the heat, and haze, and haste, generated by its reaction upon Mr.
Martineau's own mind, often produce vagueness where precision is the
one thing needful--poetic fervour where we require judicial calm; and
practical unfairness where the strictest justice ought to be,