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:
“For all Men would be Cowards if they durst:
And Honesty’s against all common sense—”
—John Wilmot, 2d Earl Of Rochester (1647–1680)
“Behold now this vast city; a city of refuge, the mansion house of liberty, encompassed and surrounded with his protection; the shop of war hath not there more anvils and hammers waking, to fashion out the plates and instruments of armed justice in defence of beleaguered truth, than there be pens and hands there, sitting by their studious lamps, musing, searching, revolving new notions.”
—John Milton (1608–1674)
“What had really caused the women’s movement was the additional years of human life. At the turn of the century women’s life expectancy was forty-six; now it was nearly eighty. Our groping sense that we couldn’t live all those years in terms of motherhood alone was “the problem that had no name.” Realizing that it was not some freakish personal fault but our common problem as women had enabled us to take the first steps to change our lives.”
—Betty Friedan (20th century)
“I know, of course, how important it is not to keep a business engagement, if one wants to retain any sense of the beauty of life.”
—Oscar Wilde (1854–1900)