The Demon-Haunted World_ Science as a Candle in the Dark - Carl Sagan [126]
For myself, I’ve tended in past books to recount some of the occasions when I’ve been right. Let me here mention a few of the cases where I’ve been wrong: at a time when no spacecraft had been to Venus, I thought at first that the atmospheric pressure was several times that on Earth, rather than many tens of times. I thought the clouds of Venus were made mainly of water, when they turn out to be only 25 per cent water. I thought there might be plate tectonics on Mars, when close-up spacecraft observations now show hardly a hint of plate tectonics. I thought the highish infrared temperatures of Titan might be due to a sizeable greenhouse effect there; instead, it turns out, it is caused by a stratospheric temperature inversion. Just before Iraq torched the Kuwaiti oil wells in January 1991, I warned that so much smoke might get so high as to disrupt agriculture in much of South Asia; as events transpired, it was pitch black at noon and the temperatures dropped 4-6°C over the Persian Gulf, but not much smoke reached stratospheric altitudes and Asia was spared. I did not sufficiently stress the uncertainty of the calculations.
Different scientists have different speculative styles, some being much more cautious than others. As long as new ideas are testable and scientists are not overly dogmatic, no harm is done; indeed, considerable progress can be made. In the first four instances I’ve just mentioned where I was wrong, I was trying to understand a distant world from a few clues in the absence of thorough spacecraft investigations. In the natural course of planetary exploration more data come in, and we find an army of old ideas ploughed down by an armamentarium of new facts.
Postmodernists have criticized Kepler’s astronomy because it emerged out of his medieval, monotheistic religious views; Darwin’s evolutionary biology for being motivated by a wish to perpetuate the privileged social class from which he came, or to justify his supposed prior atheism; and so on. Some of these claims are just. Some are not. But why does it matter what biases and emotional predispositions scientists bring to their studies, so long as they are scrupulously honest and other people with different proclivities check their results? Presumably no one would argue that the conservative view on the sum of fourteen and twenty-seven differs from the liberal view, or that the mathematical function that is its own derivative is the exponential in the northern hemisphere but some other function in the southern. Any regular periodic function can be represented to arbitrary accuracy by a Fourier series in Muslim as well as in Hindu mathematics. Non-commutative algebras (where A times B does not equal B times A) are as self-consistent and meaningful for speakers of Indo-European languages as for speakers of Finno-Ugric. Mathematics might be prized or ignored, but it is equally true everywhere - independent of ethnicity, culture, language, religion, ideology.
Towards the opposite extreme, there are questions such as whether abstract expressionism can be ‘great’ art, or rap ‘great’ music; whether it’s more important to curb inflation or unemployment; whether French culture is superior to German culture; or whether prohibitions against murder should apply to the nation state. Here the questions are oversimple, or the dichotomies false, or the answers dependent on unspoken assumptions. Here local biases might very well determine the answers.
Where in this subjective continuum, from almost fully independent of cultural norms to almost wholly dependent on them, does science lie? Although issues of bias and cultural chauvinism certainly arise, and although its content is continually being refined, science is clearly much closer