Evolutionary psychology is an entire field related to the study of "instinctual" human behavior (due to evolutionary adaptations). Neuropsychology is also relevant to this and lends credence to the idea that part of who we our (our thoughts and behaviors) is not due to learning (but rather the structure and chemistry of our brains). Realistically we are a product of both sides.
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Member of DaJoGen MMA school under Dave Hagen and Team Chaos fight team under Denver Mangiyatan and Chris Toquero, ran out of Zanshin Martial Arts in Salem Oregon: http://www.zanshinarts.org/Home.aspx,