Thomas Reid: The Scottish School of Common Sense Realism Reid recognizes to some extent that Hume was not a total skeptic. Indeed, he ingenuously acknowledges, that it was only in solitude and retirement that he could yield any assent to his own philosophy; society, like day-light, dispelled the darkness and fog of scepticism, and made him yield to the dominion of common sense. (Inquiry, Chapter I, Introduction, Section V; see Hume's Treatise, Book I, Part IV, Section 7) Hume's inability to remain skeptical was taken by Reid to be an inconsistency on his part and a demonstration of the weakness of philosophical reasoning in the face of common sense. Reid held that common sense will always win the contest with philosophy, "for, in reality, Common Sense holds nothing of Philosophy, nor needs her aid" (Inquiry, Chapter I, Introduction, Section IV). Indeed, it is philosophy that stands in need of the aid of common sense to keep it from falling into skepticism. Philosophy . . . has no other root but the principles of Common Sense; it grows out of them, and draws its nourishment from them. Severed from this root, its honours wither, its sap is dried up, it dies and rots. (Inquiry, Chapter I, Introduction, Section VII) On the other hand, it is easy to see why philosophers would be inclined to criticize a system that takes common sense as its starting point. The views of ordinary, non-philosophical people seem to be quite unreflective and indeed riddled with error. Philosophers have tended to view their task as being to rise above the common view of things and present a more lofty picture of the universe. Reid does not fall victim to this kind of criticism, however. His account of "common sense," as outlined in the Essays on the Intellectual Powers of Man, Essay VI, Chapter 2, was itself a philosophical one. Reid begins by explaining what is "common" about "common sense." He thought that common sense is something which nearly all human beings have. The only ones who lack it are defective in some way, victims of "lunacy." A person who, through some natural mental defect, believes he is made of glass has departed from common sense. And a skeptical philosopher who does not believe that mind-independent bodies exist has similarly taken leave of common sense. The difference is that the philosopher abandons common sense not due to a mental defect, but rather due to the influence of metaphysical arguments. So Reid describes a skeptic as a victim of "metaphysical lunacy." Self-evident beliefs can be divided according to whether they are about what is necessary (what is immutable, and whose contrary is impossible) or about what is contingent (what is mutable, and whose contrary is possible). Beliefs that are self-evident and necessary are called "axioms," and they include basic beliefs about mathematics. Such beliefs are infallible. "The light of truth so fills my mind in these cases, that I can neither conceive nor desire anything more satisfactory" (Essa ...