SECT. V. OF THE IMPRESSIONS OF THE SENSES AND MEMORY.


In this kind of reasoning, then, from causation, we employ materials,
which are of a mixed and heterogeneous nature, and which, however
connected, are yet essentially different from each other. All our
arguments concerning causes and effects consist both of an impression of
the memory or, senses, and of the idea of that existence, which produces
the object of the impression, or is produced by it. Here therefore we
have three things to explain, viz. First, The original impression.
Secondly, The transition to the idea of the connected cause or effect.
Thirdly, The nature and qualities of that idea.

As to those impressions, which arise from the senses, their ultimate
cause is, in my opinion, perfectly inexplicable by human reason, and
it will always be impossible to decide with certainty, whether they arise
immediately from the object, or are produced by the creative power of the
mind, or are derived from the author of our being. Nor is such a question
any way material to our present purpose. We may draw inferences from the
coherence of our perceptions, whether they be true or false; whether they
represent nature justly, or be mere illusions of the senses.

When we search for the characteristic, which distinguishes the memory
from the imagination, we must immediately perceive, that it cannot lie in
the simple ideas it presents to us; since both these faculties borrow
their simple ideas from the impressions, and can never go beyond these
original perceptions. These faculties are as little distinguished from