But while psychodynamicists speculated about non-empirical hypothetical “mental” constructs, behavioristic researchers studied the real empirical constructs of stimuli and responses. Others such as D. O. Hebb and Wilder Penfield in the 1940’s and 50’s operated on non-human brains to see how the brain mediated Ss and Rs, and then tried to generalize their scientific results to human psychology. Ironically, some of the greatest breakthroughs in understanding how normal “minds” work came through the analysis of abnormal human psychology, demonstrated by the wounded brains (and consequent pathologies of thought, feelings, and actions) of soldiers from World War II and Korea.
Gradually, scientists’ findings — and their very successful applications to real world problems — turned the tide away from non-scientific toward scientific psychology, ushering in the late 20th century’s explosion of breakthrough theories and treatments and making real progress for the first time. One important turning point was the publication of D. O. Hebb’s book in 1949, which theorized in detail from a strictly scientific perspective how brain cells determined specific functions of human cognition.
Once a significant number of scientists began to study the human brain — instead of NECs of the “mind” — breakthroughs leading to a true understanding of the causes and effects of human psychology followed relatively rapidly.
Today, scientific psychology has discovered many of the natural laws and principles that really govern “human nature;” i.e., how and why people think, feel, and act as they do in general, and — given sufficiently valid individual information — why any specific person thinks, feels, and behaves as s/he does. (In psychology as in all sciences, the better the data, the better the theories and the more accurate and useful the resulting predictions and interventions.)
For one example, we now know the basic answer to the age-old “nature versus nurture question”: i.e., are good (and bad) people “born that way” — and thus presumably unable to change; or do their environments “make them that way” — so that changing their environments can presumably change their psychology? The answer is both! We now know that all human psychology is governed by three (yes, only three) natural determinants:
our genes (our DNA and RNA — deoxyribonucleic acid and ribonucleic acid, respectively), which pre-program our psychological instincts and potential capabilities, and predispose us to develop particular ways of thinking, feeling, and acting;
our learning (conditioning through environmental experience), which programs and re-programs exactly what we think, feel, and do; and
our trauma (central nervous system damage), which can re-program and even de-program our repertoire of thoughts, feelings, and behaviors.