Today investors believe in the size premium on the basis of empirical evidence, not on theoretical arguments. (researchaffiliates.com)
The experiment would be only for the benefit of those against whom you are arguing here, since evidently theoretical arguments don't work for them and they are demanding experiments. (judithcurry.com)
So the evidence comes from observations, through theoretical arguments about the greenhouse effect, and through models. (carbonbrief.org)