An intuition a lot of people have is:
- The extinction of a species is a very bad thing.
- If species at least typically arise by evolutionary processes, (1) is false.
What can we say given (2)? Well, we could argue:
- Species at least typically arise by evolutionary processes. (Scientifically known fact)
- Therefore, the extinction of a species is not a very bad thing. (By 2 and 3)
Another move is to argue:
- Both (1) and (2) are true.
- Therefore, species do not arise by evolutionary processes, even typically. (By 5)
- If species do not arise by evolutionary processes, creationism is true. (Since creationism is the best alternative to evolution.)
- So, creationism is true. (By 6 and 7)
A yet different move is to deny (2). My thinking behind (2) was based on the value of diachronic biodiversity. But perhaps diachronic biodiversity is only as valuable as I think it is if presentism is false. It is only if the past organisms in extinct species really exist, even if pastly so, that they contribute in a valuable way to biodiversity. So one might replace (2) by:
- If species at least typically arise by evolutionary processes and presentism is false, (1) is false.
- Claims (1) and (3) are true.
- Therefore, presentism is true. (By 9 and 10)
So I think we have three main options:
- Deny that extinction is a very bad thing.
- Deny evolution and affirm creationism.
- Affirm presentism.
I should note that in (1), I am thinking of on-balance badness rather than just intrinsic badness.