Beyond The Theoretical Dilemma Of Evolutionary Psychology

Evolutionary psychology (EP) becomes a new approach to psychological researches in recent years. As a result of combining the modern evolutionary biology and cognitive psychology, EP aims to discovery the internal characteristics of human mind from the evolution and adaptation. Otherwise, EP is always involved in all kinds of debates since it was born. Some researchers claim that EP brings a whole revolution which will make EP become a promising psychological paradigm. On the contrary, others consider EP as a replica of sociobiology, just like "old wine in a new bottle". Now the number of EP’s empirical researches keeps increasing, in which good and bad experiments were mixed. Actually, these debates mostly come from ambiguity and limitation of EP. By looking back the generation of EP’s theoretical framework, this dissertation will analysis the EP’s core theories from psychological structure, mental processes and research methodology, and then illustrate the EP’s theoretical dilemma and experimental misunderstanding by two case studies.EP was born of the rapid development of modern evolutionary biology and psychology. In the branch of biology, some new theories provide EP with fertile ground such as the ethology, inclusive fitness theory, the reciprocal altruism, parental investment theory, and sociobiology. With the development of infant’s cognitive abilities theory and domain-specific trend, evolutionary psychologists return to the traditional functionalism thought. Besides, EP’s theoretical framework also benefits from the extensive discussion about crisis of psychology, multi-paradigms, scientific objectivism and humanism.Adaptations theory is EP’s point of view on psychological structure. It derived from Jerry Fodor’s "modularity of mind", Cosmides and Tooby’s "Swiss-Army Knife model", Sperber and Samuels’s "massive modules theory", and evolved psychological mechanism (EPM) theory. According to adaptations theory, human mind consists of a series of EPM, and every adaptation will be evolved to deal with some specific adaptive problem. This theory has some flaws as follow:(1) it couldn’t examine the ontogeny and development of psychological mechanism from dynamic perspective;(2) it blows hot and cold about domain-general psychological mechanism although it has denied Fodor’s module theory;(3) it couldn’t explain the interaction and work mode of all independent adaptations;(4) different kinds of adaptations and adaptations’ grain problem.EP describes mental processes as Darwinian algorithm. That means every EPM will only receive specific information, and process these data according to internal program and decision rules. The output will provide some results to help organisms to solve specific adaptive problems. In essence, Darwinian algorithm continues to use the concepts of cognitive psychology about computation and representation. It can’t escape from the troubles of computation theory, but only narrow the scope and capacity of computation. Added to the reductionism, EP has to confront these problems, such as computability of mind, relation of syntax and semantic, intentionality of mind.There are two general methodologies in EP, reverse engineering and multilevel analysis method. The former has three steps,(1) determine the adaptive problems that human ancestor faced repeatedly,(2) determine the adaptation’s function by analysis the adaptive problem,(3) examine the intrinsic structure and work mechanism. The latter divides EP’s research program into four levels, such as general evolutionary theory, middle-level evolutionary theory, specific evolutionary hypothesis, and specific predictions derived from hypothesis. There are two strategies of generating and testing evolutionary hypothesis, top-down strategy and bottom-up strategy. In general, these two methodologies have to face the following problems:(1) there isn’t one to one correspondence between functions and structures, and it doesn’t work that speculating the structures from the functions;(2) psychological adaptations have experienced dynamic development, and one can’t work backwards from the mature form to original character of adaptations;(3) it’s hard to be operationalized for many specific evolutionary hypothesis, and have to face the problem of being unfalsifiable;(4) EP has no any new research technologies, and EP’s research value will decrease to some extent because of using too much questionnaires.Although it has to face many problems, EP brings some new thoughts to us. EP is deserved to be praised because of the following reasons:(1) EP helps some folk psychological knowledge to enter into the region of scientific psychology, which extend greatly the sphere of psychology;(2) EP gets rid of the relativism derived from Behaviorism;(3) EP reshapes the wrong dichotomy of "nature-nurture";(4) EP points out the defects of cross-culture theory about variations of mind;(5) EP will bring some new results if researchers choose the right variables and methods prudently.In sum, EP can’t be considered as a new paradigm for psychology now, although it is still a useful perspective. The evolution theory will continue to nourish psychology in future. A mature EP needs the support from other disciplines such as paleoanthropology, cognitive neuroscience, and embodied cognition theory.