Louis Pasteur on Life

Question from Truk:
Evolution directly contradicts Pasteur’s laws, that state life can only come from life, as well as the laws of thermodynamics. Why does evolution, a flawed theory with more holes in it than a sponge, still stand, when it contradicts proven science?

Answer by SmartLX:
If evolution contradicted proven science, it wouldn’t still stand. That’s the whole point of science: if it’s proven wrong, it changes. The biology departments of the universities of the world don’t have the resources to maintain a massive conspiracy to prop up a bogus theory, but they have the evidence to support a sound one.

Thermodynamics first: you haven’t specified which laws you think evolution contradicts, so I’ll assume you mean the Second Law of Thermodynamics. There are several creationist arguments based on this idea, and I’ve addressed two of them here, here and here. If I haven’t covered your specific objection, comment and tell me what it actually is.

Now for the less run-into-the-ground material. Louis Pasteur only produced one “law”, and even that is only tentatively attributed to him: the Law of Biogenesis, which states that life can only come from other life. Pasteur did make such an observation, whether or not he made it official. The competing hypothesis of the day was spontaneous generation, the idea that life springs from non-life everywhere, all the time. People used to think that a bag of grain would spontaneously generate maggots, for instance. Pasteur examined many apparent examples of this, and in every case discovered that life was somehow getting in from outside and propagating.

Pasteur did not demonstrate, nor could he have, that it’s impossible for life to emerge from non-life in any circumstances. He simply established that it does not happen in everyday life, and that the life all around us is far more connected than people once thought. If genetics had been further along at the time he could have known this for certain, because all known life is genetically related and therefore descended from a single organism, a common ancestor.

This fact has an important implication: all life on earth can be explained by a single ancient event of abiogenesis (literally genesis from non-life). This means it’s to be expected that the circumstances in which abiogenesis can occur are incredibly rare, and might not even exist in the present day. However, given a billion years, half a billion square kilometres of surface area and countless different chemical compounds on this planet, it’s not unreasonable to suppose that the elements of life came together in just the right way, at least once. Living tissue doesn’t contain any element which isn’t also found in non-living material; it is literally made of the things around it.

Abiogenesis isn’t part of the theory of evolution anyway, because that’s only concerned with what life has done since it came about. Even if a god had created the first living thing, evolution could have occurred from then on without the god’s help, producing all the diversity of life from that single organism. This isn’t important to you though, Truk, because you want to establish that at least some part of the process was impossible without divine help, necessitating the existence of the divine. Abiogenesis, while unlikely in any single moment and circumstance, is not so unlikely that it can’t have happened naturally at all, so a god isn’t needed there either. Better keep looking for a spot to force one in.

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