ret
uneasiness lest for scorn so loudly expressed he had not brought forward
adequate justification. And the reader feels that Diderot has scarcely
hit the true line of cleavage that would have enabled him--from his own
point of view--to shatter the Spinosist system. He tries various bouts
of logic with Spinosa in connection with detached propositions. Thus he
deals with Spinosa's third proposition, that, _in the case of things
that have nothing in common with one another, one cannot be the cause of
the other_. This proposition, Diderot contends, is false in all moral
and occasional causes. The sound of the name of God has nothing in
common with the idea of the Creator which that name produces in my mind.
A misfortune that overtakes my friend has nothing in common with the
grief that I feel in consequence. When I move my arm by an act of will,
the movement has nothing in common in its nature with the act of my
will; they are very different. I am not a triangle, yet I form the idea
of one and I examine its properties. So with the fifth proposition, that
_there cannot be in the universe two or more substances of the same
nature or the same attributes_. If Spinosa is only talking of the
essence of things or of their definition, what he says is naught; for it
can only mean that there cannot be in the universe two different
essences having the same essence. Who doubts it? But if Spinosa means
that there cannot be an essence which is found in various single
objects, in the same way as the essence of triangle is found in the
triangle A and the triangle B, then he says what is manifestly untrue.
It is not, however, until the last two or three pages that Diderot sets
forth his dissent in its widest form.

"To refute Spinosa," he says at last, "all that is necessary is to stop
him at the first step, without taking the trouble to follow him into a
mass of consequences; all that we need do is to substitute for the
obscure principle which he makes the base of his system, the following:
namely, that _there are several substances_--a principle that in its own
way is clear to the last degree. And, in fact, what proposition can be
clearer, more striking, more close to the understanding and
consciousness of man? I here seek no other judge than the most just
impression of the common sense that is spread among the human race....
Now, since common sense revolts against each of Spinosa's propositions,
no less than against the first, of which