Epicurus’ view was that we consist of atoms (though what he meant by this term was a bit different from what modern scientists mean by it). Once these atoms come apart at death we no longer exist as individuals capable of consciousness. Even if someone could carefully put all the bits back together again later, and breathe life back into this reconstructed body, it wouldn’t be anything to do with me. The new living body wouldn’t be me, despite looking like me. I wouldn’t feel its pains, because once the body ceases to function nothing can bring it back to life. The chain of identity would have been broken.
(A little history of philosophy - Nigel Warburton)
Why did the author use "would have" in "The chain of identity would have been broken"? I don't understand the usage in this case. Could you explain this for me?