Question from Anon:
I’m engaged in a discussion with a Christian friend of mine who has presented this syllogism to me:
“1. Simply put, if there is no external cause of the universe, then the universe is either eternal or self-created.
2. But, it is cosmologically ridiculous and anti-scientific (i.e. against laws of thermodynamics) to propose that the universe is either eternal or self-created.
3. Therefore, the premise that there is no external cause of the universe must be false (i.e. there must be an external cause for the universe’s existence, e.g. God)”
I believe he is applying the law where it can’t be applied, but I’ve never extensively studied science in college so I’m not really sure.
My rebuttal was that the universe was not necessarily a closed system and he responded with this:
“I have to remind you that my academic background has required me to not only understand, but apply, thermodynamics. [He has an engineering degree.] I know what the 2nd Law of Thermodynamics means and it clearly eliminates the concept of an eternal universe. If there is any misunderstanding on my part, it is in what you mean by ‘the law of the universe.’ Further, whether the universe is a closed system or not is irrelevant, since the concept of a closed system is theoretical, i.e. we have never actually observed a closed system.”
Thanks and I hope you can sort this out for me.
Answer by SmartLX:
Well, it’s not the usual creationist argument that evolution breaks the 2nd Law simply by producing order, so at least it’s a change.
He’s got one thing right, the universe is unlikely to be self-created. We don’t know of anything that is, or even what that would mean if it were true. For an entity to be the reason for its own existence would require an exception to the idea that an effect follows its cause. Rather than call this ridiculous, however, I’d just say that time would have had to behave non-linearly near the beginning. It’s strange to consider, but it hasn’t been ruled out as far as I know.
To set up the next option a bit, an eternal universe would need to be one where multiple Big Bangs happen in sequence. We have to work from the scientific fact of the Big Bang to achieve a plausible eternal model, especially after Borde, Guth and Vilenkin successfully ruled out the leading eternal models that didn’t involve singularities.
Your friend’s thermodynamic objection to an eternal universe is that any process that’s already been running forever should have run down by now, because no process is perfectly efficient. There are at least two scenarios in which this is averted (possibilities only, mind you):
– The singularity that immediately precedes each Big Bang reclaims all of the matter and energy in the universe by bringing space itself back to a central point. This includes all of the “lost” energy that radiates from decaying systems and is normally declared unusable, so in the end nothing is truly lost and the universe really is perfectly efficient.
– Extending upon your friend’s response, not even the universe itself is a closed system. It receives energy from an outside source, such as other universes. If there is an infinite number of these as some have hypothesised, they can keep a universe such as ours going indefinitely. (If one takes “universe” to mean everything that exists, in other words the whole multiverse, then the idea is available that it may contain infinite matter and energy, and never have to run down for this reason instead. It’s all a matter of perspective, and to some extent semantics.)
As an afterword on eternal universes, it’s worth asking your friend exactly how he exempts his eternal God from the 2nd Law of Thermodynamics. I hold it to be true that whatever constraints you place on the universe to necessitate a god, you immediately have to break them to allow for the god, usually by way of special pleading.
Moving on to the third option, it’s telling that your friend’s syllogism uses “e.g.” and not “i.e.” to invoke God. God is an example of an external cause, not the only possible one. The alternative suggested by the above is a concurrent or previous universe, which is part of a great many theories out there. I would love to hear your friend’s reasoning that starts from the external cause at the end of the syllogism and arrives at the Christian God, because at a glance it’s far from a logical step. (The following isn’t a scientific argument, but additional universes seem a more plausible thing to posit than a god because at least we know there’s such a thing as a universe. If your 5-acre cabbage patch has been devoured and you find one fat little rabbit in the corner, you don’t suppose that Bigfoot ate the rest; you wonder where all the other rabbits are hiding.)
Finally, there is a fourth option not covered by the syllogism: that the universe simply came into being without being created, that the common straw-man concept of “something from nothing” actually happened. Something like this is put forward in Lawrence Krauss’ new book A Universe from Nothing; specifically, that the precursor to the universe in certain models could be thought of as “nothing”. Even if you don’t accept this as quite the same thing, it at least advances another alternative external cause to compete with God.
Most of the options are essentially still on the table, despite your friend’s attempt at an argument by elimination. Even the option he wants to be left with doesn’t help the case for God very much, if at all.
Question from Anon: