Kant Insisted That Mental Phenomena Could Not Be Studied in the Same

Kant insisted that mental phenomena could not be studied in the same way as the natural sciences were studied.One aspect of his reasoning for this was

A) it is impossible to have a priori knowledge of the human mind.
B) there is no way to empirically prove the functions of the unconscious mind.
C) mental phenomena were the concern of philosophers alone.
D) none of the above