Who Discovered The Unconscious?

Who Discovered The Unconscious?
Though definitions vary, the Unconscious can be understood to be the area of the psyche that contains thoughts, feelings and memories, which we have repressed for one reason or another. In doing so these repressed thoughts can manifest themselves through dreams, or through psychotic or neurotic behaviour.
<Tab/>As to who discovered the unconscious? Perhaps the real question is: who identified the unconscious? For surely humans have always been aware of the unconscious in some form or another, though they didn't always identify it as such. So…