Galileo debated why ice floats

Galileo once debated why ice floats:

Galileo had a lot of self-confidence, Caruana said, which helped him stand up to the church on heliocentricity, using a strong foundation of experimental data. But the scientist’s ego also led him to propose—and vehemently defend—some curiously wrong arguments too. For example, Galileo argued that comets were optical illusions (they are most definitely physical objects) and that ocean tides were the result of oceans sloshing around from Earth’s rotation (tides have more to do with the moon’s gravitational pull). His erroneous arguments during the water debate are a useful reminder that the path to scientific enlightenment is not often direct and that even our intellectual heroes can sometimes be wrong. ...

But Galileo then went too far. Aiming at the main thrust of delle Colombe’s argument, Galileo said that the shape of an object did not affect whether the object would sink or float.

Galileo had not accounted for surface tension, however. Surface tension forces can help objects located on a liquid surface resist sinking on the basis of how much of that object is in contact with the liquid’s surface. Consider a paper clip: If it is placed flat on the surface of water it can float, but if it is placed on water standing straight up, it sinks. The difference is the higher surface tension force experienced by the paper clip lying flat on the water’s surface. So in a way, the shape of an object (in contact with the surface) does contribute to whether it sinks or floats.

On the third day of the debate, delle Colombe stole the show with a crowd-pleasing experiment, Caruana said. Delle Colombe presented a sphere of ebony to the audience. The sphere was placed on the surface of the water, and it began to sink. Then delle Colombe took a thin wafer of ebony and placed it on the surface of the water, where it floated. Because the density of both the wafer and the sphere of ebony were the same, delle Colombe announced that density had nothing to do with buoyancy and that an object’s shape was all that mattered.

That’s when “the dispute became noisy and inconclusive, and the meeting was brought to a close,” Caruana said.

To my surprise, many Slash dot commenters recognize that Galileo was not so scientific in his dispute with the Pope either:

Cause the Pope had been one of his biggest supporters and protectors. And Galileo had not been able to offer proof of his beliefs. Actually, more so that a number of his arguments in support were disproven (such as the tides sloshing about).

So basically, the Pope said you can discuss, but not advocate for the heliocentric view as a fact. Instead, Galileo, published a book arguing for it, and using some of the Pope's statements by a character named Simpleton.

This is like a venture capitalist saying "Please don't say we've discovered a cure for cancer. Until we have proved that it works. Instead, just say we are 'researching' a cure for cancer."

Then the researcher goes on the View. And well, a lot of the stuff he claims as proof of success is circumstantial and invalid. ...

Even after Galileo was placed under house arrest for publishing his work as fact instead of theory (which is what the dispute was about), the Church provided housing for him, built him an observatory, fed him, provided servents for him, paid him to do research and a host of other things. It was probably the most comfortable house arrest in history.

If Galileo had stuck to established science, he would not have had trouble.