a? To believe
or affirm any thing, it is necessary, at least, to know in what it
consists. To believe in the existence of your immaterial soul, is to
say, that you are persuaded of the existence of a thing, of which it is
impossible for you to form any true notion; it is to believe in words
without meaning. To affirm that the thing is as you say, is the height of
folly or vanity.

104.

Are not theologians strange reasoners? Whenever they cannot divine the
_natural_ causes of things, they invent what they call _supernatural_;
such as spirits, occult causes, inexplicable agents, or rather _words_,
much more obscure than the _things_ they endeavour to explain. Let us
remain in nature, when we wish to account for the phenomena of nature; let
us be content to remain ignorant of causes too delicate for our organs;
and let us be persuaded, that, by going beyond nature, we shall never
solve the problems which nature presents.

Even upon the hypothesis of theology, (that is, supposing an all-powerful
mover of matter,) by what right would theologians deny, that their God
has power to give this matter the faculty of thought? Was it then more
difficult for him to create combinations of matter, from which thought
might result, than spirits who could think? At least, by supposing matter,
which thinks, we should have some notions of the subject of thought, or of
what thinks in us; whereas, by attributing thought to an immaterial being,
it is impossible to form the least idea of it.

105.

It is objected against us, that materialism makes man a mere machine,
which is said to be very dishonourable. But, will it be much more
honourable for man, if we should say, that he acts by the secret impulses
of a spirit, or by a certain _I know not what_, that animates him in a
manner totally inexplicable.

It is easy to perceive, that the supposed superiority of _spirit_ over
matter, or of the soul over the body, has no other foundation than men's
ignorance of this soul, while they are more familiarized with _matter_,
with which they imagine they are acquainted, and of which they think they
can discern the origin. But the most simple movements of our bodies are to
every man, who studies them, as inexplicable as thought.

106.

The high value, which so many people set upon spiritual substance, has no
other motive than their absolute inability to define it intelligibly. The
contempt shewn for _matter_ by our metaphysicia