The Galileo affair and settled science


Everyone knows the Galileo story.

The Italian astronomer Galileo Galilei, who lived from 1564 to 1642 and was the first to use a telescope to make astronomical observations, got himself crosswise with the Catholic Church by proclaiming that the sun stood still and the earth moved around it, rejecting the prevailing view that the earth stood still and the sun moved around it. This earned him a heresy trial before the Italian Inquisition, which ended on June 22, 1633 (381 years ago a week from next Sunday) with him recanting his views under duress and being placed under house arrest for the last nine years of his life.

The affair has been a huge embarrassment for the Church in modern times — an iconic example (so to speak) of theology lashing out in denial at empirically discovered reality that contradicts scripture and its worldview.

That pretty much sums up the prevailing view of the Galileo affair. However, there is one small problem with this narrative: With regard to the science at the core of the case, the Church wasn’t completely wrong and Galileo wasn’t completely right.

The late John W. Campbell, editor of Astounding Science Fiction from 1937 until 1971, had a fascinating take on the Galileo affair. The gist of his argument went like this:

The Church had heartburn with Galileo over two specific issues, Campbell said. One was Galileo’s assertion that the earth circled the sun. The other was his assertion that the sun stood still at the center of creation.

Of the two, the assertion that the earth circled the sun, rotated on its axis, and did not stand still at the center of creation was the less serious. That, in the Church’s view was “absurd and false philosophically” and “theologically considered at least erroneous in faith.” However, it did not consider this assertion to be formal heresy.

Galileo’s assertion that the sun did not circle the earth but stood still at the center of creation was another matter, however. Not only did the Church consider this “absurd and false philosophically,” it also considered it “formally heretical, because it is expressly contrary to the Holy Scripture.”

(The quoted phrases in the two previous paragraphs are taken the actual sentence passed on Galileo on June 22, 1633, as quoted in Giorgio De Santillana’s book The Crime of Galileo.)

However, as Campbell pointed out, we know today that while the earth goes around the sun, the sun does not stand still. It moves through the galaxy, circumnavigating it every 225 to 250 million years or so. Moreover, the galaxy itself moves through space. So on the issue of the sun standing still at the center of creation, the Church was right; the sun does not stand still and it is not the center of the universe.

Of course, the Church and Holy Scripture were wrong on how the sun actually moved. And it was wrong in its view of the earth’s place in creation and its supposed absence of movement.

Galileo for his part was wrong on the question of solar movement because his cosmology, while more accurate than that of the Church, was insufficiently broad to accommodate the concept of solar movement in addition to planetary movement.

Campbell thought modern science should take this dimension of the Galileo affair as a cautionary tale — that it should recognize that even its greatest and most fundamental discoveries should be accepted somewhat conditionally and subject to change it the light of future discoveries. And above all, that the notion of “settled science” should always be regarded with some suspicion and skepticism.

Biology provides a modern example of a scientific heretic who history has correctly judged a charlatan being partially right and “settled science” being partially wrong.

The late Russian biologist Trofim Lysenko, who believed seeds and plants could acquire traits like resistance to cold and drought by being exposed to cold and dry conditions — and then could pass these traits on to the next and future generations. In terms of the prevailing understanding of genetics for most of the 20th century, this was scientific heresy; the belief that traits came from the genes an organism inherited from its parents, and that environmental stresses couldn’t change them, was settled science.

Lysenko nevertheless succeeded in convincing Stalin of his views — and of the need to silence his critics, many of whom were imprisoned and sent to labor camps. Criticizing Lysekoism was made a crime in 1948. In the Soviet Union, the views of the heretic became holy writ and settled science.

But Lysenko’s attempts to demonstrate the inheritability of acquired characteristics failed; the failures were eventually unmasked, and he was disgraced and marginalized. The judgment of history has been that he set back biology in Russia by a generation.

And he did, by poisoning the wellsprings of honest scientific inquiry. But the modern understanding of biology suggests that Lysenko may have been partially right. It is true that the genes an organism inherits are largely unchanged from generation to generation, but more recently it has been discovered that genes can be turned on and off in response to environmental stresses — and that a gene that an organism inherited in the “on” state can be passed on to the next generation in the “off ” state and vice-versa.

The discovery that genes can be turned on or off in response to factors from outside an organism has given rise to the field of epigenetics, which is revolutionizing contemporary biology. And it also provides a mechanism by which environmentally acquired inheritance might take place.

Lysenko might have set Russian biology back a generation but that doesn’t change the fact that on the core question of whether an organism can acquire a trait from interaction with its environment and then pass it on to subsequent generations, he had a point — even if his own experiments failed to bear it out.

Given what was known at the time, conventional biology was right to reject Lysenko’s views. But modern biology should be honest enough to acknowledge that in retrospect he was not completely wrong, even if he was an asshole, and that it was not completely right — and that in science the worst and most enduring heresy is the phrase “settled science.”


This opinion column does not necessarily reflect the views of Boulder Weekly.