changing, ever vanishing, impenetrable to thought alone, to which
it exhibits only its disguises? Materialist! I permit you to
testify to the reality of your sensations; as to what occasions
them, all that you can say involves this reciprocity: something
(which you call matter) is the occasion of sensations which are
felt by another something (which I call spirit).



[5] Chemists distinguish between MIXTURE and COMPOSITION, just
as logicians distinguish between the association of ideas and
their synthesis. It is true, nevertheless, that, according to
the chemists, composition may be after all but a mixture, or
rather an aggregation of atoms, no longer fortuitous, but
systematic, the atoms forming different compounds by varying
their arrangement. But still this is only an hypothesis, wholly
gratuitous; an hypothesis which explains nothing, and has not
even the merit of being logical. Why does a purely NUMERICAL or
GEOMETRICAL difference in the composition and form of atoms give
rise to PHYSIOLOGICAL properties so different? If atoms are
indivisible and impenetrable, why does not their association,
confined to mechanical effects, leave them unchanged in essence?
Where is the relation between the cause supposed and the effect
obtained?

We must distrust our intellectual vision: it is with chemical
theories as with psychological systems. The mind, in order to
account for phenomena, works with atoms, which it does not and
can never see, as with the ME, which it does not perceive: it
applies its categories to everything; that is, it distinguishes,