I think that the greatest proof that time travel isn't possible is that we're not overrun by now! We're running around the clock, saving people's lives for sure.
But I can't prove time travel is possible!
Time travellers have invented absolutely nothing, and we're just getting started. But I can at least prove time travel is possible. I'll demonstrate it by doing experiments!
T-Rex, this is a very pressing concern!
Our last words will be "T-Rex, you saved our lives!"
Experimentations?
Sure, but the point is, any experiments we do will have to be recorded and used to build a computer so we can travel to this future and save people's lives, and get them back before it's destroyed.
Experimentations are important!
But not mandatory!
Okay, fine, OBVIOUSLY. We've got to do experiments.
We're gonna need a time machine.
That'll take us from here and back in time, and make us the smartest and most perfect being thus far.
That's not an amazing premise!