The human capacity for comprehending the nature of reality . In Plato 's theory of knowledge, we comprehend the truths of mathematics through understanding. For modern philosophers following Descartes or Locke , the understanding is the intellectual faculty considered more broadly or generally. Also see OCP . The formal fallacy committed in a categorical syllogism that is invalid because its middle term is not distributed in either premise.
Some mammals are whales.
Therefore, some dogs are whales. Also see OCP and GLF . Hume pointed out that such uniformity is presupposed by all of our belief in matters of fact , Mill identified several practical methods for recognizing its instances, but Goodman raised a significant paradox of induction . Also see OCP and BGHT . Therefore, all spaniels are dogs.