2 de setembro de 2009

Biology and Ethics

Publica-se o resumo da conferência plenária que o Prof. Francisco Ayala irá proferir no Congresso Internacional sobre o Impacto de Darwin na Ciência, na Sociedade e na Cultura (Faculdade de Filosofia de Braga, 10-12 Setembro)

Ayala, Francisco J. University of California, Irvine, USA, The Biological Foundations of Ethics

The question whether ethical behavior is biologically determined may refer either to the capacity for ethics (i.e., the proclivity to judge human actions as either right or wrong), or to the moral norms accepted by human beings for guiding their actions. I will propose: (1) that the capacity for ethics is a necessary attribute of human nature; and (2) that moral norms are products of cultural evolution, not of biological evolution.

Humans exhibit ethical behavior by nature because their biological makeup determines the presence of three necessary conditions for ethical behavior: (i) the ability to anticipate the consequences of one's own actions; (ii) the ability to make value judgments; and (iii) the ability to choose between alternative courses of action.

Ethical behavior came about in evolution not because it is adaptive in itself, but as a necessary consequence of man's eminent intellectual abilities, which are an attribute directly promoted by natural selection. That is, morality evolved as an exaptation, not as an adaptation.

Since time immemorial, human societies have experimented with moral systems. Some have succeeded and spread widely throughout humankind, like the Ten Commandments, although other moral systems persist in different human societies. Many moral systems of the past have surely become extinct because they were replaced or because the societies that held them became extinct.

The moral systems that currently exist in humankind are those that were favored by cultural evolution. They were propagated within particular societies for reasons that might be difficult to fathom, but that surely must have included the perception by individuals that a particular moral system was beneficial for them, at least to the extent that it was beneficial for their society by promoting social stability and success. Acceptance of some precepts in many societies is typically reinforced by civil authority (e.g., those who kill or commit adultery will be punished) and by religious beliefs (God is watching and you’ll go to hell if you misbehave). Legal and political systems, as well as belief systems, are themselves outcomes of cultural evolution.


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