The world that we think we see is only our best guess. - Margaret Atwood

She doesn't think it's a good idea to know the future, because you can hardly ever change it, so why suffer twice?

We may call Eurydice forth from the world of the dead, but we cannot make her answer; and when we turn to look at her we glimpse her only for a moment, before she slips from our grasp and flees. As all historians know, the past is a great darkness, and filled with echoes. Voices may reach us from it; but what they say to us is imbued with the obscurity of the matrix out of which they come; and, try as we may, we cannot always decipher them precisely in the clearer light of our own day.

Every habit he's ever had is still there in his body, lying dormant like flowers in the desert. Given the right conditions, all his old addictions would burst into full and luxuriant bloom.