Einstein hypothesized that, if something could travel faster than the speed of light, it would break fundamental physical laws by being able to observe, relatively speaking, a stationary electromagnetic wave. Thus, for his theory of relativity to work, he hypothesized that the speed of light must remain constant.
Other people trying to conquer you instead. If you come across competitors who are crossing the same route, that could mean war for money, gold and an assortment of other things.
The book "I have Lived a Thousand Years" provides evidence against the Holocaust deniers, as it presents a detailed, personal story of life through holocaust, which many details that are corroborated by others.
