In the past 125+ years, it might be suggested that, all certainty aside, we have only reclaimed "a little more land"........................

"The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexplicability. Our business in every generation is to reclaim a little more land, to add something to the extent and the solidity of our possessions."

-Thomas Henry Huxley, as excerpted from his 1887 essay, On The Reception of the Origin of Species

thanks David