Who would have been most likely to say: "why you behave the way you do is because of unconscious reasons, not reasons in your consciousness?

I believe the answer is: Sigmund Freud

According to sigmund Freud's theory, every individuals have underlying unconscious mind that become the basis of every behavior that we made everyday. 
This unconscious thought influence our decision without our awareness and often reflected our true feeling about the things that happening around us even though we may tell otherwise.