Do we sense our surroundings first or do we start interpreting and reacting to them right away? Logically we are tempted to assume that we first sense our environment and then interpret it.

For example when you see this symbol - 'µ' - its commonsense to believe that we first perceive its shape, color, etc. and then interpret it to be 'Mu'; but those events may not be happening in that order after all.

We tend to interpret as we sense and vice-versa. The final perception seems to be a mix of both actual and assumed details and our brains must have evolved this mechanism to reduce reaction times.

Nowhere is this phenomenon more evident than in the case of dyslexics and synesthetes. While dyslexics have trouble seeing symbols as depicted, synesthetes perceive symbols in varying colors irrespective of the color they are actually depicted in.

Obviously if we are seeing first and interpreting later, Dyslexia and Synesthesia are logically impossible.