Full Idea
Armstrong has argued that experience, as normally understood, is not necessary to perception. To perceive is to acquire beliefs, through a causal process.
Clarification
This makes non-conscious perception a possibility
Gist of Idea
Maybe experience is not essential to perception, but only to the causing of beliefs
Source
report of David M. Armstrong (Belief Truth and Knowledge [1973]) by Roger Scruton - Modern Philosophy:introduction and survey 23.4
Book Reference
Scruton,Roger: 'Modern Philosophy: introduction and survey' [Sinclair-Stevenson 1994], p.336