David_Brayton

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I am not normally a nit pick (well, maybe I am) but this jumped out at me: an example of a fact--"whether Earthly life arose by natural selection." Because natural seletion is one of the cornerstones of modern biology, I thought I'd take a few seconds to enter this comment.

Natural selection is a biological process by which favorable traits that can be gentically inherited become more common in successive generations of a population of reproducing organisms, and unfavorable traits that can be inherited become less common. The driving force is the need to survive. So, for example, cheetahs that can run faster because of inheritable traits catch more food and tend to live so as to pass on the traits.

So, natural selection doesn't say anything about how life arose. As a factual matter, the example is a non sequitur.

You might have been thinking of "common descent". From Wikipedia: "A group of organisms is said to have common descent if they have a common ancestor. In biology, the theory of universal common descent proposes that all organisms on Earth are descended from a common ancestor or ancestral gene pool."

But, common descent doesn't say how life arose. It says that all life on Earth can be traced back to one initial set of genes/DNA. How that initial pool of chemicals became what we call life is not addressed by common descent.