Rick Perry Versus the True Believers
As for that vaunted "consensus" of climate scientists that supposedly proves the truth of AGW, Giaever summed it up this way:
Global warming has become a new religion. We frequently hear about the number of scientists who support it. But the number is not important: only whether they are correct is important.
And speaking of correctness -- Perry also made a remark about global warming and Galileo that evoked similar ridicule from the press and the left side of the blogosphere. A particularly prominent example was the Atlantic's James Fallows, who called Perry's statement, made during the most recent Republican debate, "flat-out moronic."
Here's what Perry actually said:
[T]he science is...not settled on this. The idea that we would put Americans' economy at...jeopardy based on scientific theory that's not settled yet, to me, is just -- is nonsense....[J]ust because you have a group of scientists that have stood up and said here is the fact, Galileo got outvoted for a spell....Find out what the science truly is before you start putting the American economy in jeopardy.
Fallows further mocks Perry by comparing him to a person who says, "Hey, I'll mention Galileo! Unfortunately in mentioning him, I'll show that I don't know the first thing about that case...." But although Fallows may think that he's the one who really knows the first thing about Galileo, he may not know the second and the third thing -- including what the Church's main beef with Galileo was, and the position of Galileo's scientific contemporaries on the subject of heliocentrism. The latter is especially important to Perry's analogy, since he was talking about disagreements among scientists, both in Galileo's time and now.
The Church had initially become upset with Galileo for two main reasons, neither of them the conventional "church vs. science" objection of legend. His first offense was committing theological overreach in their eyes when he stated that heliocentrism did not contradict the Bible because scripture should not be interpreted literally. The second was a kind of scientific hubris: Galileo's assertion that heliocentrism had been proven (incontrovertibly, as it were) rather than being a tentative working theory. In addition, many of Galileo's fellow scientists, although split on the matter, were more against Galileo than with him, just as Rick Perry said. The reason for their skepticism was not theology, it was that Galileo's model was inconsistent with the best empirical observations of the time -- although of course, in retrospect, his theory turned out to be correct.
The most important problem with Galileo's heliocentric theory, and one that was widely recognized by his scientific contemporaries, was the lack of "observable parallax shifts in the stars' positions as the earth moved in its orbit around the sun." It was only much later that instruments were designed that were sensitive enough to detect the shifts. Therefore, Galileo lacked scientific evidence to prove his theory, and many leading astronomers of the day rejected it. The renowned Tycho Brahe was one of them; he had his own competing theory, which was a Geo-Heliocentric hybrid in which the sun revolved around the earth but the other planets revolved around the sun, a system that conformed better than Galileo's with the lack of observed stellar parallax and which remained in scientific favor for a long time.
I have written that Galileo's theory turned out to be correct, but that is actually an over-simplication. Galileo was indeed correct in stating that the planets revolve around the sun. But he also believed that the sun is the fixed and unmoving center of the universe, which we now know to be incorrect.
This error does not contradict the fact that Galileo was a scientific giant. But the story is a reminder that even the brilliant make mistakes, and that science does not advance by simple progression from ignorance to perfect knowledge, nor is it proven by consensus. It moves in fits and starts, sometimes with small wavering steps and meanderings, sometimes with great leaps. Sometimes it lingers for a while in blind alleyways. But it is always incomplete, and must continually be tested and questioned.