Why Is the Infinite Regress Not Convincing?

Phaser defends that at length in his book Five Proofs. The causal chain is essential, not accidental in nature. Since it can't undergo change, the actualizer must be timeless and immaterial. It must be necessary because it has no potential for non-existence. If there were two purely actual actualizers, then neither could be purely actual. Each of them would have to exist in a common framework more basic than either of them. And it would be this framework that ultimately explain reality, not the actualizers.