Ammonius Quotes (1 quote)
There are reported to be six species of metals, namely, gold, silver, iron, copper, tin, and lead. Actually there are more. Mercury is a metal although we differ on this point with the chemists. Plumbum cinereum (gray lead) which we call bisemutum was unknown to the older Greek writers. On the other hand, Ammonius writes correctly many metals are unknown to us, as well as many plants and animals.
As translated by Mark Chance Bandy and Jean A. Bandy from the first Latin Edition of 1546 in De Natura Fossilium: (Textbook of Mineralogy) (2004), 19. Originally published by Geological Society of America as a Special Paper (1955). There are other translations with different wording.
In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
(1987) -- 
