But in this brightest and kindest world, the philosophical problems themselves become intimidating. A mind that stays at the same capacity cannot live forever; after a few thousand years it would look more like a repeating tape loop than a person. (The most chilling picture I have seen of this is Larry Niven’s story “The Ethics of Madness.”) To live indefinitely long, the mind itself must grow … and when it becomes great enough, and looks back … what fellow-feeling can it have with the soul that it was originally? The later being would be everything the original was, but vastly more. And so even for the individual, the Cairns-Smith or Lynn Margulis notion of new life growing incrementally out of the old must still be valid.

An obvious metaphysical question to raise here is the compatibility or otherwise of religion and transhumanism. In my 1990 essay that first set forth modern transhumanism as a distinct philosophy under that name, I explained how transhumanism (like humanism) can act as a philosophy of life that fulfills some of the same functions as a religion without any appeal to a higher power, a supernatural entity, to faith, and without the other core features of religions (More 1990). The central place accorded to rationalism suggests a tension between transhumanism and religion. But are they actually incompatible? Since rationalism is an approach to acquiring knowledge and says nothing about the content of knowledge, it is possible in principle for a transhumanist to hold some religious beliefs. And some do. The content of some religious beliefs is easier to reconcile with transhumanism than the content of others. Christian transhumanists, while not completely unknown, are very rare (and I know of none who are fundamentalists, and such a combination would surely indicate deep confusion). There are more Mormon transhumanists (although some of these are cultural rather than religious Mormons), perhaps because that religion allows for humans to ascend to a higher, more godlike level, rather than sharply dividing God from man. Several transhumanists describe themselves as Buddhists (presumably of the secular, philosophical type), and there seem to be few obstacles to combining transhumanism with liberal Judaism. However, the vast majority of transhumanists do not identify with any religion. A pilot study published in 2005 found that religious attitudes were negatively correlated with acceptance of transhumanist ideas. Those with strong religious views tended to regard transhumanism as competing with their beliefs (Bainbridge 2005).