Quote:
Originally Posted by xelasnave
Chemistry although not fully understood yet suggests life is a natural consequence from chemical reactions and if such is valid the suggestion would be life could well be found in many places other than Earth.
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I don't think Dirac's purported quote is at odds with this. All Alex seems to be saying is that the chemical pathway that changes non-living into living is not understood but evidence suggests that such a pathway would be followed where ever suitable conditions are found. This is a pretty common opinion.
In many peoples' view there is only one basic chemical pathway and so life only occurs in water in the Goldilocks zone. Isaac Asimov speculated that life may arise over a much wider temperature range than Goldilocks could endure and to do this it may be based in different solvents. He argued that the chemical building blocks (basically protein in our case) must be sufficiently stable at the ambient temperature but not inert. For example at somewhat lower temperatures than we live in proteins become unreactive but lipids (fats and oils) are now sufficiently stable that they could become the basis of life. I forget the details of what he suggested for each temperature range but I think that at the upper end - many hundreds to thousands C - it was some 'exotic' fluorine compounds.