While not a household name, or a Hollywood type publicity hound of the media as he is actually a bit of a recluse who has given most of his life to the study of philosophy. However the fact that he lived most of his adult life boarded up in a room at All-Souls College in Oxford (England) even while most of this time married (to Janet Radcliff Richards also a philosopher) , its what he has spent his time waxing on which make him worth writing about. The topic you ask, while its “Time” as yes we’ve waxed and wained about it yesterday so it only made sense to carry it forward today as Parfit has some interesting views and they may be right in a startling fashion.
As one of the thing Parfit postulates is the identity of future generations. As he puts forward that one’s existence is intimately related to the time and conditions of conception. As you would not be you if your parents waited another year to have a child. While they would still have had a child, it would certainly be another being; even if it were still their first born (assuming you are), it still would not be you.
Let us take for example the concepts of Global Warming for a minute (also yes there is such a thing, take a peek at Greenland on Google Earth, its green that’s bad) to which we will relate to the romantic involvement of future childbearing partners, our children for short. Here if we play this out, what happens is that any actions taken today, will affect the resulting people that exist after only a few generations. As this being a significant environmental impact could shift the initial conditions of the conception process so much that after 300 years none of the same people that would have been born are in fact born. As different couples meet each other and conceive at different times—different people will therefore exist. Parfait refers to this as the ‘non-identity problem.’
Here disastrous policies could be enacted that would be worse for nobody, because none of the same people exist under the different policies. It’s here parfait allows us to consider the moral ramifications of potential policies in person-affecting terms, as if the case we will have no reason to select a sound policy over an unsound one provided that its effects are not felt for a few generations. As this describes the non-identity crisis in its purest form: the identity of future generations is causally dependent, in a very sensitive way, on the actions of the present generations. In fact to such an extent they effectively have no identity if one peers as little as 50 years into the future. As philosophers have long ignored this problem and thus devised systems of [meta] ethics that are powerless to argue against current temporally biased policies.
In short, Parfit argues with this the sins of the present hurt no one, as the ones they would hurt won’t exist because of the present sins. However the future is wholly different then the present, yet one has to wonder is this not Darwin’s natural selection at work…