A Defence of Common Sense is an influential 1925 essay by philosopher G. E. Moore. In it, he attempts to refute skepticism by arguing that at least some of our beliefs about the world are absolutely certain. Moore argues that these beliefs are common sense.
In section one, he argues that he has certain knowledge of a number of truisms, such as "My body has existed continuously on or near the earth, at various distances from or in contact with other existing things, including other living human beings", "I am a human being", and "My body existed yesterday".
In section two, he argues that there is a distinction between mental facts and physical facts. He says there is no good reason to hold, as many philosophers of his time did, that every physical fact is logically dependent on mental facts, or that every physical fact is causally dependent on mental facts. An example of a physical fact is "The mantelpiece is at present nearer to this body than that bookcase is." Mental facts include "I am conscious now" and "I am seeing something now."
In section three, he affirms that not only does he not think there are good reasons for believing that all material objects were created by God, but neither does common sense give reasons to think that God exists at all or that there is an afterlife.
The fourth section considers how common sense propositions like "Here is my hand" are to be analysed. Moore considers three possibilities that occur to him for how what we know in these cases is related to what we know about our sense-data, i.e. what he sees when looking at his hand. Moore concludes that we are absolutely certain about the common sense belief, but that no analysis of the propositions has been offered that is even close to being certain.
The fifth section is an examination of the problem of other minds. Moore argues that "there are other 'selves'", but explains why this question has baffled philosophers. In other words, the sense data that he perceives through his senses are facts about the interaction of the external world and himself, but he (and other philosophers) do not know how to analyze these interactions.
Famous quotes containing the words common sense, defence, common and/or sense:
“Common sense tells us that the things of the earth exist only a little, and that true reality is only in dreams.”
—Charles Baudelaire (1821–1867)
“To choose a hardship for ourselves is our only defence against that hardship. This is what is meant by accepting suffering.... Those who, by their very nature, can suffer completely, utterly, have an advantage. That is how we can disarm the power of suffering, make it our own creation, our own choice; submit to it. A justification for suicide.”
—Cesare Pavese (1908–1950)
“The greatest waste of time he knew of was to count the hours—what good can come of it?—and the greatest illusion in the world, to lead one’s day by the sound of the clock, and not by precepts of common sense and understanding.”
—François Rabelais (1494–1553)
“No slave is a slave to the same lengths, and in so full a sense of the word, as a wife is.”
—John Stuart Mill (1806–1873)