"Robbing from your future self"
He boggled. "You can't just take dope for the rest of your life, son. Eventually, something will happen to this body--I see from your file that you're stroke-prone--and you're going to get refreshed from your backup. The longer you wait, the more traumatic it'll be. You're robbing from your future self for your selfish present. (Doctorow, Down and Out in the Magic Kingdom 162)
This almost sounds like a conversation between a parent and child (the doctor does call Julius "son," after all). It reminds me of the kind of talk a parent would have with an irresponsible child who is 'throwing his life away' by refusing to grow up and take responsibility for his own wellbeing. It's strange, because you'd think there's no sense in distinguishing between your present self and your future self in Doctorow's fictional world--you never die--but for Julius, it's a distinction that makes all the difference. The doctor, too, seems like he's drawing a division between the two, but it's only for the sake of convenience; it really has nothing to do with the two very different lives of who Julius is now and who he might be when his fresh upload is complete.