As Christians, we must believe life is a gift, the greatest gift, from God, as recounted in Genesis. If God is omniscient and omnipotent, as we believe Him to be, we cannot dictate the terms of His gift to us, otherwise we are questioning His supernal qualities and making Him one of us. If he really is one of us, however, we really don't need Him, do we? We can handle matters quite well without Him, can't we? If we do so, however, we are playing God ourselves, and unfortunately we are just not that good at it.
Consider the following quotation then guess who owns it.
Today, however, civilization has brought sympathy, pity, tenderness and other lofty and worthy sentiments, which interfere with the law of natural selection. We are now in a state where our charities, our compensation acts, our pensions, hospitals, and even our drainage and sanitary equipment all tend to keep alive the sickly and the weak, who are allowed to propagate and in turn produce a race of degenerates.
Give up? Those are the words of the patron saint of feminism, Margaret Sanger (you won't find them on the website of Planned Parenthood, the institution she founded, nor will you find mentioned the fact she accepted an invitation from the K.K.K. to speak about the very "problem" of which she wrote: the "race of degenerates"). The "civilization" and the attendant qualities she questions are, of course, Christianity and Christian charity. I would not accuse +Butler of espousing such hideous notions as Sanger's, he surely does not, but unless one is uncompromising when it comes to the sanctity of life, it is all too easy to slip into thinking thoughts as, "Surely God did not intend this person to suffer so" or "Isn't keeping this poor soul alive costing a lot of money that could be better spent elsewhere?" Thence leads to the murderous philosophy of Utilitarianism and its weaseling proponents like Peter Singer (a professor of bioethics at Princeton!) and from there it is but a short journey to Final Solutions.
I have a cousin who was born paralyzed from the neck down but blessed (or cursed) with a first-class mind. The difficulty of her life I cannot begin to fathom but she bears her burden well and manages to possess a wicked sense of humor. Still, I wonder if +Butler, upon witnessing the protracted suffering my cousin has gone through in her life would think that it would have been better she had not been born or allowed to live. I hope, at least, he would ask her first.