I’m noticing that the word “random” seems to often be a hangup in discussions here. So I want to say a little about randomness that I hope might clear the air.
I’m an agnostic
Let’s first clear the air about my agnosticism. I’m going to be talking about God, so you need to know that I am agnostic. It’s not just that I say I don’t know whether there’s a god. It is more that I doubt the possibility of knowing that there’s a god. So when I comment on whether God could use randomness, best to understand that have no commitments to there being a god.
I’ll start with two examples of randomness.
Example 1: the lottery
We mostly know about lotteries. You buy a lottery ticket. And it is a matter of luck as to whether you win.
Would God use a lottery? As an agnostic, I don’t have a say on this. However, it does seem unlikely that the Abrahamic God would use a lottery. And this seems to be one of the objections that some folk have to evolution. They see “random” cropping up in discussions of evolution, and they worry that this implies that their God is depending on a lottery-like use of randomness. Einstein’s famous “God does not play dice” about QM was a similar reaction. As far as I know, Einstein was atheist or agnostic.
Example 2: baking a cake
You want to bake a cake. So you put the ingredients in a bowl. And then you stir them up.
Stirring up that cake batter is a process of randomization.
This is very different from the lottery example. When you play the lottery, you hope for a lucky but unlikely result. When you stir up the cake batter, your aim is that it turn out to be rather even and uniform. You are not looking for a lucky outcome. Stirring (i.e. randomization) is just a good way of getting a pretty uniform batter and a good cake.
If God were baking a cake, would God stir up the batter? Or would God micromanage where every molecule goes? Or would God come up with a special supernatural form of stirring, so that He could just stir up the batter in such a way that He could then micromanage where every molecule goes?
As an agnostic, I don’t know. But I think I prefer the kind of God that would just stir up the batter, and not attempt to micromanage at the molecular level.
Randomness in evolution
So how is randomness used in evolution? Is it more like the lottery idea? Or is it like the cake batter example? Or is it somewhere in between?
People disagree about this. The neutral theory seems to be closer to the lottery example. My own view of evolution is closer to the cake batter example.
I try to look at it from the vantage point of a population (of organisms). The population depends on a particular ecological niche. And the risk for the population is that the environment is always changing. And it could change in a way that eliminates the niche being used by the population.
The “intelligent” thing for the population to do, would be to prepare for the possibility that the environment will change. One way of doing this, is to have some variation within the genetics of the population, so that at least some part of that population might survive the environmental change. We normally think of the variation as arising from mutations. But the population cannot guess the future. So it cannot guess what particular mutation would work. So the best that it can do is “mix it up” and have mutations favoring many possible directions. And then see which work better as the environment changes. So that’s a use of randomness that seems like stirring the cake batter.
We also see meiosis, and crossovers that occur during meiosis. That’s a kind of randomization that results from sexual reproduction. And it is really a mixing up of variation already existing in the population.
Additionally, we see transpositions. A piece of DNA is transposed to a different part of the genome. Perhaps what was previously junk DNA is transposed to where it might become active. And the junk DNA may have originated as a DNA segment that was once useful in the past history of this population. So there’s an apparent stirring up of memories of formerly useful DNA segments.
The critics of evolution see random as bad, something like luck or something like noise. But the use of randomness can also be intelligent, as in when we stir the cake batter.
My hope is that this post, and subsequent discussion, will help people broaden their ideas about how randomness is used in evolution.