Final Cause

For Thomas, the “final cause” is the first cause. That is, the purpose for which a thing is done is what initiates doing the thing. I plan to retire to Tahiti; that is my final purpose. And that is the cause that initiates the various schemes of earning and saving that I embark on. The final end is the initiating cause.

This sounds odd to modern ears. Causes are supposed to precede effects and not to follow them. So we put mental quotation marks around “cause” in “final cause,” and assume that cause in the strict sense is always efficient cause. But why? Is that not already to concede to a mechanistic cosmology? Isn’t the introduction of “final cause” as a true cause, and indeed as initial cause, a key way to preserve the personalism of our cosmology?