Archer writes:
It's a fatal self-contradiction..... Death by suicide
Yeah but is it a suicide bomb? That is, if the statement is false does it take the rest of metaphysical machinations with it.
Reexamining Hume's statement
Hume writes:
If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames: for it can contain nothing but sophistry and illusion. An Enquiry Concerning Human Understanding
He is clearly using hyperbole for effect. I don't think he meant it as some clear cut axiom, but more of a general principle.
For the Christian antagonist here, when Christ says "If you desire to be perfect go and sell all that you have, and give to the poor, and you shall have wealth in Heaven". You do not find many Christians following that axiom to the letter.
Also Hume is a bit more concise and specifies "divinity or school metaphysics". The term "philosophy" is somewhat nebulous and I found no less than 8 different connotations in the definition. Therefore i don't believe references to Philosophy of Science really apply to this discussion.
All this talk reminds me of a movie i recently watch with my wife on Father Damien and his work with lepers. My wife was quite impressed with this man's life and dedication. However when they mentioned that he thanked God very much for letting him die of the disease I realized that he was wallowing in the suffering for suffering sake. What I took from this story is that the true 'saints' where the men and women who discovered the cure to Leprosy using empirical methods and eliminated unimaginable suffering rendering faith-based workers unnecessary.
This contrasts the usefulness of 'divinity' and the 'school metaphysics' to that of the empirical accretion of knowledge and understanding.