I'm going to propose that we're all the wild imaginings of my uncle Ernie, and when he drops his cigar in his lap and wakes up with his crotch on fire we're all fucked.
Originally Posted by Belimawr
as for artificially advancing a race, while it does seem a good concept you lose survival of the fittest (something the human race lost a long time ago) so you end up with a race getting weaker and less useful, machines and medical science have allowed the weak to live and it undone millions of years of evolution as we lost the need for those skills
Is the fact that we're above natural selection not testament to the fact that we are
the fittest? Against most other animals our senses are relatively dull: we've no huge teeth or sharp claws; no natural armour; walking upright means our soft underbodies are exposed to attack - but our strength is in our ability to use tools, communicate, work together and change the world to suit us
, rather than change to suit the world.
With greater understanding of genetics we could eventually eradicate all genetic illnesses which you fear will become more prevalent as we keep the 'inferior' alive - and with the ability to modify ourselves we could evolve in the way we want, much faster than random mutation and natural selection allows. We could even adapt into different 'classes' of human depending on what purpose we wish to serve.
Things are probably relatively primitive at the moment, but I still think our current direction is preferable to going back to our more bestial roots. Don't know how this relates to time travel, though.
/off topic tangent