A Água Viva e a Teoria da Escolha Racional

Querido diário:

Volta e meia dou umas olhadas nos livros de Isaac Azimov, pois adoro os de ficção científica e os de divulgação científica. Falo hoje, novamente, de New Guide to Science, um Penguin Book de, talvez, 1984.

Ele diz na p.753:

The function of the nerve cell is so subtle and complex that even at the simple level we ara already a little beyond our depth when it comes to explain just what happens. [...] Whatever the stimulus [sobre a célula nervosa, claro], it sets up a tiny nerve impulse [sic], an electric current that progresses rapidly along the fiber. When it reaches the end of the fiber, the impulse jumps a tiny gap (sinapse) [sic] to the next nearest cell; and so it is transmitted from cell to cell. (In well-developed nervous systems, a nerve cell may make thousands of synapses with its neighbours.) [sic] In the case of a coelenterate, such as a jellyfish, the impulse is communicated throughout the organism. The jellyfish responds by contracting some part of all of its body. If the stilulus is contact with a food particle, the organism enguls the particle by contraction of its tentacles.

All this is strictly automatic, of course, but since it helps the jellyfish, we like to read purpose into the organis's behavior. Indeed, humans, as creatures who behave in a purposeful, motivated way, naturally tend to atrribute purpose even to inanimate nature. Scientists call this attitude teleological, and try to avoid such a way of thinking and speaking as much as they can. But in describing the results of evolution, it is so convenient to speak in terms of development toward more efficient ends tha teven among scientists all but the most fanatical purists occasionally lapse into teleology. [...]

Que posso dizer? A água-viva não é um bicho racional, não é mesmo? Mas age como se tivesse um propósito, uma senda motivacionada. E um cachorro? Também. E seu melhor amigo (ou melhor, dizem que o cão é o melhor amigo do homem, mas o melhor amigo do cão seria outro cão...), o homem? E que dizer de pessoas de baixa renda? E de alta renda? E de qualquer idade? E de graus de cultura física diferentes? Claro que todo mundo age, na maior parte do tempo, como se tivesse propósito, motivação.

DdAB
Imagem daqui.