The Collaborative International Dictionary of English v.0.48:

Introspection \In`tro*spec"tion\, n. [Cf. F. introspection.]
   A view of the inside or interior; a looking inward;
   specifically, the act or process of self-examination, or
   inspection of one's own thoughts and feelings; the cognition
   which the mind has of its own acts and states;
   self-consciousness; reflection.
   [1913 Webster]

         I was forced to make an introspection into my own mind.
                                                  --Dryden.
   [1913 Webster]