Representative Theory of Perception, also known as Indirect
realism, epistemological dualism, and The veil of perception, is
a philosophical concept. It states that we do not (and cannot)
perceive the external world directly; instead we know only our
ideas or interpretations of objects in the world. Thus, a
barrier or a veil of perception prevents first-hand knowledge of
anything beyond it. The "veil" exists between the mind and the
existing world. The debate then occurs about where our ideas
come from, and what this place is like. An indirect realist
believes our ideas come from sense data of a real, material,
external world (unlike idealists). The doctrine states that in
any act of perception, the immediate (direct) object of
perception is only a sense-datum that represents an external
object. Aristotle was the first to provide an in-depth
description of indirect realism. In On the Soul he describes how
the eye must be affected by changes in an intervening medium
rather than by objects themselves. He then s