In a recent thread, A_Nony_Mouse suggests that we should not at all be impressed by the fine-tuning of the universe. He suggests that it's easy to produce big numbers, and he uses an example:
If there are 10^7 sperm cells 'racing' to fertilize an egg, the chance of any sperm cell fertilizing the egg is 1:10^7. But here you are, despite the odds! Nony says we should not be so impressed by this, and so we should not be impressed by the small chances of a life-prohibiting universe either.
This is a flawed argument.
Any given sperm cell would result in a unique human being. Any number of possible constants would result in a unique universe.
It is certain that a unique human being will be born. The chances of a unique human being (given that the egg was fertilized and carried to term) are 1:1. The chances of unique possible human being A (me, say) are 1:10^7, as are the chances of unique possible human being B. So my chances versus the chances of another possible unique human being are not 1:10^7, but rather 1:1.
Similarly, the chances of the unique set of universal constants A obtaining may be equal to the chances of unique set B obtaining. But that is not what we're talking about in the fine-tuning argument. This is where Nony's analogy ends.
Here, a simple example will make the point:
If you have 10,000 different pennies in a bag, and you draw one penny, are you surprised? No, and rightfully so. Given that there is a penny draw, you will necessarily draw a unique penny. Yes, the chances of that penny being drawn are 1/10,000, but so are the chances of any and all the other pennies.
Now, imagine you have 10,000 pennies in a bag, with only one painted blue. You reach in and draw the blue penny, are you surprised? Yes, and rightfully so. What is the difference? The penny had a 1/10,000 just like any other penny, it seems nothing has changed. This is not the case, however. Here, we are not comparing any unique penny to any other unique penny. Here, the comparison is between a blue penny and non-blue pennies. So, in the first case, the chance of a unique penny being drawn is 1, it is certain. All the pennies are unique in the first example, whichever you draw will be unique and that's not impressive. In this second case, however, the chance of drawing the blue penny is 1:10,000.
(Uniqueness is a feature of all pennies in both examples, and so any penny drawn will be unique; blueness is a feature of only a single (unique) penny, and it is BLUENESS that we are asking about in the second example).
The fine-tuning argument does not seek to say the chance of any unique universe with its constants existing is 1: 10^n. That wouldn't say much, at all. It would be the equivalent of the first penny example and of Nony's sperm-cell example.
Fine-tuning compares life-permitting universes to non-life-permitting universes. This scenario is the equivalent of the second (blue) penny example. It is not equivalent to Nony's example.
Disregarding other aspects of this argument, it should at least be admitted that Nony's analogy is fallacious and misleading. It does not hold.