<< Ah yes, but we're not as ignorant as we were then. I honestly believe time travel is impossible, and my #1 evidence is that nobody from the future has visited us yet. >>
Sure we are. We're just ignorant about different things.
Saccharine is good for you. No, wait a minute, it causes cancer.
Fen-phen is the next wonder drug. Sorry, it causes strokes.
Eggs are bad for you. No, they're not. Yes, they are. Uhmmm...
Picture our descendants 100 years from now looking back on medical procedures like chemotherapy and amputations. We'll be considered barbaric. With advances like genetic profiling and nanotechnology they may be able to eliminate surgery entirely, or at least the way we perceive it now using a scalpel.
Every culture throughout history has considered itself the most advanced of it's age. Which it was, for the time. However, state of the art only lasts for so long before being outdone. Looks at computers. Good ol' Moore. It's just as hard for us to predict the future now as it was for our ancestors hundreds of years ago. Just because it hasn't happened yet doesn't mean that it won't happen. "Commissioner of Patents Henry Ellsworth wrote in the Annual Report for 1843: 'The advancement of the arts, from year to year, taxes our credulity, and seems to presage the arrival of that period when human improvement must end.' Do you think that we've reached the point that human improvement has ended? Or will we continue to advance?