""There is a way to fool the weighing-test", Isaac said. "Impossible! Nothing is heavier than gold!" "I have discovered the existence of gold of greater than twenty-four-carat weight." "That is an absurdity", Daniel said, after a moment's pause to consider it. "Your mind, being a logical organ, rejects it", Isaac said, "because, by definition, pure gold weighs twenty-four carats. Pure gold cannot become purer, hence, cannot be heavier. Of course, I am aware of this. But I say to you that I have with my own hands weighed gold that was heavier than gold that I knew to be pure". From any other man on earth --Natural Philosophers included-- this would amount to saying "I was sloppy in the laboratory and got it wrong". From Sir Isaac Newton, it was truth of Euclidean clarity."