A psychology without heredity.

The “enduring mission” of Zing‐Yang Kuo to eliminate the nature–nurture dichotomy in psychology

“…He revised his position by questioning the validity of heredity in psychology (Kuo, 1924, 1929). He first questioned the nature of heredity as a scientific concept.…”

“…After all, biological studies of heredity dealt with definite and quantifiable bodily characteristics, not abstractions. As he put it, “heredity of behavior can never be proved as long as there is no one‐to‐one correlation in a fixed, definite, and invariable way between neuromuscular patterns and behavior patterns” (1924, p. 438). In other words, studies on the heredity of behavior would be required to link specific, fixed behaviors with definite, underlying physio‐morphological (e.g., neuromuscular) patterns, along with an explanation of the mechanisms by which germ cells generate the latter.…”

“…Thus, “the instinct psychologists ends his investigation where the non‐instinct psychologist begins” (1922, p. 350). In a similar vein, the use of heredity by psychologists (which was not tied to morphological facts) was, according to Kuo (1924), a vague, unverifiable abstraction that allowed psychologists to sidestep or explain away experimental psychophysiology and developmental psychology.…”

Ontogeny

“…He does, however, appear to have been influenced by these critics in his later, near total, repudiation of both human and animal instincts. By 1925, for example, following the repeated critiques of Kuo (1921Kuo ( , 1924) ( see below) Watson suggested that "habit formation starts in all probability in embryonic life . .…”

“…A related and equally long-standing issue in philosophy and psychology, concerning behavioral development, is the dispute between the so-called nativists and empiricists over-depending on the period in history-innate vs. acquired ideas, nature vs. nurture, instinct vs. learning, heredity vs. environment, and maturation vs. experience. In view of the widely accepted fundamental nature of these two issues in the history of biology and psychology it is surprising that there has never been a single, detailed study tracing the growth and interrelationship of the biological ideas of preformation and epigenesis on the one hand, and the related psychological issues on the other. That such a relationship exists is obvious from the frequency with which one encounters the terms preformation (or predetermination) and epigenesis applied to specific views of neural and behavioral development (see, for example, Kuo, 1924Kuo, , 1929Kuo, , 1970Carmichael. 1925;Maier and Schneirla, 1935;Hunt, 1961Hunt, .…”