Two great fallacies in science

AI Thread Summary
The discussion highlights two significant misconceptions in the history of science. First, it argues that Galileo did not discover the principle that all bodies fall at the same rate; instead, he demonstrated it experimentally using an inclined plane, building on ideas from Lucretius. Second, it clarifies that Darwin's theory of natural selection is often misrepresented by the phrase "survival of the fittest," which was actually coined by Herbert Spencer and misapplied to Darwin's work. The conversation also touches on the complexity of scientific history and the importance of focusing on concepts rather than the origins of ideas. Overall, the thread emphasizes the need for a nuanced understanding of scientific developments and their historical context.
Keith Mackie
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The first is taught universally (as far as I can make out) at school and university, that Galileo discovered that all bodies (at least in vacuum) fall at the same rate. He didn't. He read it in Lucretius' great work of Roman science "De Rerum Natura" published about 60 BC. Lucretius followed Epicurean atomic theory and derived the fact from first principles. Since he was aware that different bodies eg feather and stone, fall at different rates, he went on to recognise air resistance. I believe that Galileo's contribution was to demonstrate the fact experimentally (not using the Tower of Pisa) but by using the inclined plane to slow down gravity. I've never been able to find a good reference (in English) to Galileo's experimental work to confirm this.

The second is Darwin and "survival of the fittest" (SoF). Darwin's theory was about "natural selection" (NS) about which he was delightfully vague - and correctly so given the state of science in his day - and not about SoF. I'm pleased to see that modern texts are moving away from reference to SoF although "fitness" seems more intractable to removal. To put it crudely, in Heisenbergian terms, NS is to Speciation what quantum theory is to classical physics.

SoF was invented by a railway engineer turned philosopher, Herbert Spencer. To be fair, most of his work seems to have been quite sensible. When he read "Origins" he immediately sided with Huxley as one of Darwin's great defenders and attempted to explain NS with SoF drawing on his deterministic railway engineering experience. He got it hopelessly wrong and has misled the world ever since. There is no such thing as "survival of the fittest" anywhere - except perhaps in sorting machines. In writing this, as an engineer, I like to think that "it takes one to know one".
 
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Welcome to PF!

I'm not sure I get your point. Are you saying that the history of science is more complicated than is taught at first pass in school? Sure it is. So what? Comparatively little time is spent on hisory lessons: most is spent learning the theories themselves, since the history isn't really all that imporant.
 
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I agree with Russ.

Herbert Spencer wrote about evolution before Darwin but he wrote about survival of the fittest after reading Darwin's Origin of Species. At the end of the day it's the concept that matters most not who invented it. Darwin probably gets more attention because he wrote for the general public, something he has in common with Hawking.

Surprised you didn't mention the debate over who was first to fly. It's possible to have very long heated arguments on that subject but it depends entirely on your definition of flight.
 
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These are not fallacies "in science" but rather in history of science, as told in popular presentations.
There are many other examples in history, and not necessary related to science.
 
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