PSacramento: Scientific truth 200 years ago was that man couldn't fly.
You seem to confuse your personal perspective with reality. Personal belief is not reality unless what is believed in exists in reality. I am not just talking about religion here but any concept that exists only in the mind and has no external existence.
Man still cannot fly. He has invented machines that can. Remove the machines and he stays on the ground. Without the right equipment, a delude man who thinks he can fly, will still fall to his death.
Truth never changes but reality does. Reality is what is real at the time. Animals that could not fly before, have evolved wings and can now. Truth has not change but reality has.
A bird with a broken wing cannot fly. Once it heals it can. Truth has not change but reality has because truth takes place in the present only.
Yesterdays truth is not today's truth but to be truth it has to be true at the time it is called truth.