undergo infinite variations....

You see, therefore, how and why I think that the human body is a part of
Nature. As regards the human mind, I believe that it also is a part of
Nature; for I maintain that there exists in Nature an infinite power of
thinking, which, in so far as it is infinite, contains subjectively the
whole of Nature, and its thoughts proceed in the same manner as
Nature--that is, in the sphere of ideas. Further, I take the human mind
to be identical with this said power, not in so far as it is infinite,
and perceives the whole of Nature, but in so far as it is finite, and
perceives only the human body. In this manner, I maintain that the human
mind is part of an infinite understanding.

_The Nature of the Human Mind_

The essence of man is formed by certain modes of the attributes of God,
that is to say, modes of thought, the idea of all of them being prior by
nature to the modes of thought themselves; and if this idea exists,
other modes (which also have an idea in nature prior to them) must exist
in the same individual likewise. Therefore an idea is the first thing
which forms the Being of the human mind. But it is not the idea of a
non-existent thing, for then the idea itself could not be said to exist.
It will therefore be the idea of something actually existing. Neither
will it be the idea of an infinite thing, for an infinite thing must
always necessarily exist, and this is absurd. Therefore the first thing
which forms the actual Being of the human mind is the idea of an
individual thing actually existing.

The knowledge of everything which happens in the object of any idea
necessarily exists in God, in so far as He is considered as modified by
the idea of that object; that is to say, in so far as He forms the mind
of any being. The knowledge, therefore, necessarily exists in God of
everything which happens in the object of the idea constituting the
human mind; that is to say, it exists in Him in so far as He forms the
nature of the human mind; or, whatever happens in the object of the idea
constituting the human mind must be perceived by the human mind; in
other words, an idea of that thing will necessarily exist in the human
mind. That is to say, if the object of the idea constituting the human
mind be a body, nothing can happen in that body which is not perceived
by the mind.

If the body were not the object of the human mind, the ideas of the
modifications of the body would not be in