Is 20°C twice as hot as 10°C? Now, I know that the phenomenon (heat) described by 20°C is by no means twice as intense as is that described by 10°C. Yet 20 is also undoubtedly twice the size of 10, no more and no less. So we have two seemingly opposing ways of looking at the situation. Which one is correct, and what standards do we use to judge that correctness? Or is there no correct answer?