Earth in Upheaval, the Supplement, page 267
In the fields of archaeology, geology, and astronomy the last few years have brought a vast array of facts to corroborate the claims made in Worlds in Collision that there were physical upheavals of a global character in historical times; that these catastrophes were caused by extraterrestrial agents; and that the nature of these agents may be identified. What I want to impress upon you is that science today, as in the days of Newton, lies before us as a great uncharted ocean, and we have not yet sailed very far from the coast of ignorance.
Don't be afraid to face facts, and never lose your ability to ask the questions: Why? and How? Be in this like a child. Don't be afraid of ridicule; think of the history of all great discoveries. I quote Alfred North Whitehead: "If you have had your attention directed to the novelties of thought in your own lifetime, you will have observed that almost all really new ideas have a certain aspect of foolishness when they are first produced."
Persist if you see the facts gathering on your side. It may be that even the strongest opposition, that of figures will crumble before the fact. The greatest mathematician who ever walked on these shores, Simon Newcomb, proved in 1903 that a flying machine carrying a pilot is a mathematical impossibility. In the same year of 1903 the Wright brothers, without mathematics, but by a fact, proved him wrong. The truth of today was the heresy of yesterday.