The answer to this covers a broad spectrum of approaches in the field of psychology. On one extreme of the spectrum is the approach that claims that human nature is completely determined by genetic "hard wiring," meaning that everything we are, from intelligence to criminal tendency, is pre-determined by genetically inherited DNA sequences. This is the Biological Approach and is advocated by "nativist" scientists like Galton and Jenson and Chomsky. On the other extreme of the spectrum is the approach that claims that nature is completely determined by the effect and influence of the environment one is reared in. This is the Behavioralist Approach and is advocated by "empiricist" (materialist) scientists like Skinner (of "tabula rosa" "blank slate" fame) and Bandura.
In between are approaches that adapt varying degrees of each extreme to an approach that combine, in one degree or another, the concepts of both the extremes. Holding the middle ground is the approach of Cognitive Psychology that identifies mental constructs as hard-wired but qualifies this by asserting that the hard wiring can be continually modified by environmental factors.
In between the Biological Approach and the Cognitive Approach lies Freud's Psychoanalytical Approach, which emphasizes sexual impulse and aggression. On the other side of the middle ground, in between the Cognitive Approach and the Behavioralist Approach, lies the Humanist Approach, which emphasizes a hierarchy of biological needs working with social influence impacting the development of self-concept.