The discussion is indeed moving off topic, nonetheless:
Constantinos:
I have to side with Tom on this one. The statement that "F = ma is a mathematical truth" might be "true by definition", however, if you think this truly describes the behavior of objects like rockets, then you are mistaken. When I was studying physics, in grad school, a former college roommate wrote to me thus: I just formulated the motion of a rocket, as a differential equation, starting with the equation F=ma. When I solved this equation, I obtained an absurd result. What is wrong? I quickly verified his absurd result (Try it! Solve the equation). What is wrong? Hint: Even in the classical case, F=ma is valid only if "m" does not change. But most of "m", for a rocket, consists of the fuel, which is rapidly burned away, so that "m" does change.
John and Tom:
Up until about 1800, it was assumed, by most biologists, that the number of species existing in the world could never change; existing species could never go extinct and new ones could never appear, because it was thought that would disrupt the perfect order of the world, created by God. Then, something was discovered in the USA. Much later, it was identified as a fossilized Mastodon tooth. But at the time, no one had any idea what it was, until a slave, from Africa, noted that it resembled an elephant tooth. Since it was assumed that species could not go extinct, it was concluded similar creatures must still be alive. So Thomas Jefferson ordered Lewis and Clark to look for it, while on their western expedition. Their inability to find one, prompted some to begin to seriously consider that some species had disappeared. But if species could disappear, why could they not also appear? But how would they appear? That was the question of the age. Finding the answer is what put Darwin and Wallace "on the map".
Rob McEachern