Tuesday, May 26, 2009

Arguments XXVII -- The Law of Biogenesis

One of the frequent posters on Topix has been using the "Law of Biogenesis" as an explanation of why Evolution is false. Of course you might have guessed, I couldn't disagree with him/her more.
The Law of Biogenesis simply stated is 'Life comes from Life' Back a while ago there was a belief that complex life appeared from nothing. A pile of clothes on the floor could birth a mouse. Maggots on meat would become flies. This belief was known as 'Spontaneous generation'. It held that life arising from non-life was an everyday and common occurrence. This idea was popularized by Aristotle and pretty much lasted for over 2 thousand years.

Louis Pasteur, and others, formulated and experimented an alternative to spontaneous generation in which life is required to spawn the examples of life. Flies laid eggs, which became maggots and eventually new flies. Mold was caused by microorganisms. Fermentation was also caused by microorganisms. Eventually Spontaneous Generation was disproven and replaced by the Germ Theory and other scientific theories that offered much more comprehensive and predictable explanations. They also led to many changes in practices which helped prevent spoilage and disease. Pasteur's work along these lines is frequently summed up as "Omne vivum ex ovo, Latin for all life [is] from eggs".

In modern terms it is usually expressed as 'complex life arises from complex life' or 'modern organisms do not spontaneously arise in nature from non-life'. In other words flies, mice, and even mold requires other life to be present, eggs, spores, or even parents. They do not spring up from nothing.

This 'Law of Biogenesis' does not, and never has addressed, how life started on this planet. The law of Biogenesis is fully compatible with the Theory of Evolution, since it is reproducible life that evolves and changes. So as an argument that evolution never took place, it's a pretty weak one.

Now the argument that Abiogenesis never took place is equally as weak. Pasteur was not addressing how life on Earth started, but how life gave the appearance of coming from nowhere in everyday activities. There are a number of hypotheses addressing how life may have started on Earth, all fall under the heading of 'Abiogenesis', life from non-life. Abiogenesis is not a re-telling of the myth of 'spontaneous generation' but the study how why the evidence shows that at one time there was no life on Earth and now there is a rich diversity of life. Evolution explains the diversity, but it does not address how it started. While we have developed molecules that evolve and even compete, we are still a long way from determining just how life started.

One final note. The poster who is currently using this line of argument, clearly keeps mischaracterizing it and just ignores any correction. He/she clearly objects to evolution on religious grounds -- based on other posts -- and is looking for any reasoning that can support that position. What I find really amusing is that even if, by some miracle, he/she managed to disprove evolution . . . that still would not advance his particularly narrow religious view of how life started and continues. Plus the very fact they are looking for support tells me a lot about their confidence in their belief system.


  1. Thanks for posting on this!

    I had some interesting reactions when I pointed out that the Biblical creation story seems to assume that which Pasteur disproved, namely the idea of spontaneous generation.

  2. I remember, I was one of the commenters :-) The whole discussion of 'context of the times' was terrific.