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Existence
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In common usage, existence is the world of which we are aware through our senses, but in philosophy the word has a more specialized meaning, and is often contrasted with essence. Philosophers investigate questions such as "What exists?" "How do we know?" "To what extent are the senses a reliable guide to existence?" "What is the meaning, if any, of assertions of the existence of categories, ideas, and abstractions."
The word "existence" comes from the Latin word 'existere', meaning to appear or emerge or stand out.
The word 'exist' is certainly a grammatical predicate, but philosophers have long disputed whether it is also a logical predicate.
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Encyclopedia
In common usage, existence is the world of which we are aware through our senses, but in philosophy the word has a more specialized meaning, and is often contrasted with essence. Philosophers investigate questions such as "What exists?" "How do we know?" "To what extent are the senses a reliable guide to existence?" "What is the meaning, if any, of assertions of the existence of categories, ideas, and abstractions."
The word "existence" comes from the Latin word 'existere', meaning to appear or emerge or stand out.
The word 'exist' is certainly a grammatical predicate, but philosophers have long disputed whether it is also a logical predicate. Some philosophers claim that it predicates something, and has the same meaning as 'is real', 'has being', 'is found in reality', 'is in the real world' and so on. Other philosophers deny that existence is logically a predicate, and claim that it is merely what is asserted by the etymologically distinct verb 'is', and that all statements containing the predicate 'exists' can be reduced to statements that do not use this predicate. For example, 'A Four-leaved clover exists.' can be rephrased as 'There is a clover with four leaves.'
This philosophical question is an old one, and has been discussed and argued over by philosophers from Plato, Aristotle, through Avicenna, Aquinas, Scotus, Hume, Kant, Kierkegaard and many others.
In mathematical logic existence is a quantifier, the "existential quantifier", symbolized by ?, a backwards capital E. To symbolize "Four leaf clovers exist," mathematicians would first define predicates, P(x) = "x is a clover" and Q(x) = "x has four leaves", and then form the well-formed formula (?x)(P(x) and Q(x)).
Historical conceptions
In the western tradition of philosophy, the first comprehensive treatments of the subject are from Plato's Phaedo, Republic, and Statesman and Aristotle's Metaphysics, though earlier fragmentary writing exists. Aristotle developed a complicated theory of being, according to which only individual things, called substances fully have being, but other things such as relations, quantity, time and place (called the categories) have a derivative kind of being, dependent on individual things.
The Neo-Platonists and some early Christian philosophers argued about whether existence had any reality except in the mind of God. Some taught that existence was a snare and a delusion, that the world, the flesh, and the devil existed only to tempt weak humankind away from God.
The medieval philosopher Thomas Aquinas, perhaps following the Persian philosopher Avicenna, argued that God is pure being, and that in God essence and existence are the same. At about the same time, the nominalist philosopher William of Ockham, argued, in Book I of his Summa Totius Logicae (Treatise on all Logic, written some time before 1327) that Categories are not a form of Being in their own right, but derivative on the existence of individuals.
Early modern philosophy
The early modern treatment of the subject derives from Antoine Arnauld and Pierre Nicole's Logic, or 'The Art of Thinking', better known as the Port-Royal Logic, first published in 1662. Arnauld thought that a proposition or judgment, consists of taking two different ideas and either putting them together or rejecting them:
The two terms are joined by the verb "is" (or "is not", if the predicate is denied of the subject). Thus every proposition has three components: the two terms, and the "copula" that connects or separates them. Even when the proposition has only two words, the three terms are still there. For example "God loves humanity", really means "God is a lover of humanity", "God exists" means "God is a thing".
This theory of judgment dominated logic for centuries, but it has some obvious difficulties: it only considers proposition of the form "All A are B.", a form which logicians call universal. It does not allow propositions of the form "Some A are B.", a form logicians call existential. If neither A nor B includes the idea of existence, then "some A are B" simply adjoins A to B. Conversely, if A or B do include the idea of existence in the way that "triangle" contains the idea "three angles equal to two right angles", then "A exists" is automatically true, and we have an ontological proof of A's existence. (Indeed Arnauld's contemporary Descartes famously argued so, regarding the concept "God" (discourse 4, Meditation 5)). Arnauld's theory was current until the middle of the nineteenth century.
David Hume argued that the claim that a thing exists, when added to our notion of a thing, does not add anything to the concept. For example, if we form a complete notion of Moses, and superadd to that notion the claim that Moses existed, we are not adding anything to the notion of Moses.
Kant also argued that existence is not a "real" predicate, but gave no explanation of how this is possible, indeed his famous discussion of the subject is merely a restatement of Arnauld's doctrine that in the proposition "God is omnipotent", the verb "is" signifies the joining or separating of two concepts such as "God" and "omnipotence".
Predicative nature
John Stuart Mill (and also Kant's pupil Herbart) argued that the predicative nature of existence was proved by sentences like "A centaur is a poetic fiction" or "A greatest number is impossible" (Herbart). Franz Brentano challenged this, so also (as is better known) did Frege. Brentano argued that we can join the concept represented by a noun phrase "an A" to the concept represented by an adjective "B" to give the concept represented by the noun phrase "a B-A". For example, we can join "a man" to "wise" to give "a wise man". But the noun phrase "a wise man" is not a sentence, whereas "some man is wise" is a sentence. Hence the copula must do more than merely join or separate concepts. Furthermore, adding "exists" to "a wise man", to give the complete sentence "a wise man exists" has the same effect as joining "some man" to "wise" using the copula. So the copula has the same effect as "exists". Brentano argued that every categorical proposition can be translated into an existential one without change in meaning and that the "exists" and "does not exist" of the existential proposition take the place of the copula. He showed this by the following examples:
- The categorical proposition "Some man is sick", has the same meaning as the existential proposition "A sick man exists" or "There is a sick man".
- The categorical proposition "No stone is living" has the same meaning as the existential proposition "A living stone does not exist" or "there is no living stone".
- The categorical proposition "All men are mortal" has the same meaning as the existential proposition "An immortal man does not exist" or "there is no immortal man".
- The categorical proposition "Some man is not learned" has the same meaning as the existential proposition "A non-learned man exists" or "there is a non-learned man".
Frege developed a similar view (though later) in his great work The Foundations of Arithmetic, as did Charles Peirce. The Frege-Brentano view is the basis of the dominant position in modern Anglo-American philosophy: that existence is asserted by the existential quantifier (as expressed by Quine's slogan "To be is to be the value of a variable." — On What There Is, 1948).
In Two Dogmas of Empiricism, Quine says of classes,
Semantics
In mathematical logic, there are two quantifiers, "some" and "all", though as Brentano (1838-1917) pointed out, we can make do with just one quantifier and negation. The first of these quantifiers, "some" is also expressed as "there exists". Thus, in the sentence "There exist a man," the term "man" is asserted to be part of existence. But we can also assert, "There exists a triangle." Is a "triangle", an abstract idea, part of existence in the same way that a "man", a physical body, is part of existence? Do abstractions such as goodness, blindness, and virtue exist in the same sense that chairs, tables, and houses exist? What categories, or kinds of thing can be the subject or the predicate of a proposition?
Worse, does "existence" exist?
In some statements, existence is implied without being mentioned. The statement "A bridge crosses the Thames at Hammersmith." cannot just be about a bridge, the Thames, and Hammersmith. It must be about "existence" as well. On the other hand, the statement "A bridge crosses the Styx at Limbo," has the same form, but while in the first case we understand a real bridge in the real world made of stone or brick, what "existence" would mean in the second case is less clear.
The nominalist approach is to argue that certain noun phrases can be "eliminated" by rewriting a sentence in a form that has the same meaning, but which does not contain the noun phrase. Thus Ockham argued that "Socrates has wisdom", which apparently asserts the existence of a reference for "wisdom", can be rewritten as "Socrates is wise", which contains only the referring phrase "Socrates". This method became widely accepted in the twentieth century by the analytic school of philosophy.
However, this argument may be inverted by realists in arguing that since the sentence "Socrates is wise" can be rewritten as "Socrates has wisdom", this proves the existence of a hidden referent for "wise".
A further problem is that human beings seem to process information about fictional characters in much the same way that they process information about real people. For example, in the 2008 United States presidential election, a politician and actor named Fred Thompson ran for the Republican Party nomination. In polls, potential voters identified Fred Thompson as a "law and order" candidate. Thompson plays a fictional character on the television series Law and Order. There is no doubt that the people who make the comment are aware that Law and Order is fiction, but at some level, they process fiction as if it were fact. Another example of this is the common experience of actresses who play the villain in a soap opera being accosted in public as if they are to blame for the actions of the character they play.
A scientist might make a clear distinction about objects that exist, and assert that all objects that exist are made up of either matter or energy. But in the layperson's worldview, existence includes real, fictional, and even contradictory objects. Thus if we reason from the statement Pegasus flies to the statement Pegasus exists, we are not asserting that Pegasus is made up of atoms, but rather that Pegasus exists in a particular worldview, the worldview of classical myth. When a mathematicians reasons from the statement "ABC is a triangle" to the statement "triangles exist", she is not asserting that triangles are made up of atoms but rather that triangles exist within a particular mathematical model.
Modern approaches
According to Bertrand Russell's Theory of Descriptions, the negation operator in a singular sentence takes wide and narrow scope: we distinguish between "some S is not P" (where negation takes "narrow scope") and "it is not the case that 'some S is P'" (where negation takes "wide scope"). The problem with this view is that there appears to be no such scope distinction in the case of proper names. The sentences "Socrates is not bald" and "it is not the case that Socrates is bald" both appear to have the same meaning, and they both appear to assert or presuppose the existence of someone (Socrates) who is not bald, so that negation takes narrow scope.
The theory of descriptions has generally fallen into disrepute, though there have been recent attempts to revive it by Stephen Neale and Frank Jackson. According to the direct-reference view, an early version of which was originally proposed by Bertrand Russell, and perhaps earlier by Gottlob Frege, a proper name strictly has no meaning when there is no object to which it refers. This view relies on the argument that the semantic function of a proper name is to tell us which object bears the name, and thus to identify some object. But no object can be identified if none exists. Thus, a proper name must have a bearer if it is to be meaningful.
To adapt an argument of Peter Strawson's, someone who points to an apparently empty space, uttering "that's a fine red one" communicates nothing to someone who cannot see or understand what he is pointing to. Variants of the direct-reference view have been proposed by Saul Kripke, Gareth Evans, Nathan Salmon, Scott Soames, and others.
Existence in the wide and narrow senses
According to the "two sense" view of existence, which derives from Alexius Meinong, existential statements fall into two classes.
- Those asserting existence in a wide sense. These are typically of the form "N is P" for singular N, or "some S is P".
- Those asserting existence in a narrow sense. These are typically of the form "N exists" or "S's exist".
The problem is then evaded as follows. "Pegasus flies" implies existence in the wide sense, for it implies that something flies. But it does not imply existence in the narrow sense, for we deny existence in this sense by saying that Pegasus does not exist. In effect, the world of all things divides, on this view, into those (like Socrates, the planet Venus, and New York City) that have existence in the narrow sense, and those (like Sherlock Holmes, the goddess Venus, and Minas Tirith) that do not.
However, common sense suggests the non-existence of such things as fictional characters or places.
European views
Influenced by the views of Brentano's pupil Alexius Meinong, and by Edmund Husserl, Germanophone and Francophone philosophy took a different direction regarding the question of existence. Existentialism has been a major strand of continental philosophy in the twentieth century.
Endnotes
Further reading
- Majors, The Eternal Cycle, , Modern Classics, 1999, ISBN:none
- Plato, The Republic, translated by Desmond Lee, Penguin Classics, 2003, ISBN 0140449140, ISBN-13: 978-0140449143
- Aristotle, The Metaphysics, translated by Hugh Lawson-Tancred, Penguin Classics, 1999, ISBN 0140446192, ISBN-13: 978-0140446197
- Heraclitus, Fragments, James Hilton, forward, Brooks Hexton, translator, Penguin Classics, 2003, ISBN 0142437654, ISBN-13: 978-0142437650.
- The Meaning of Life, Terry Eagleton, Oxford University Press, 2007, ISBN 0199210705 ISBN-13: 978-0199210701
- The Story of Philosophy, Bryan Magee, Dorling Kindersley Lond. 1998, ISBN 0-7513-0590-1
- What is Existence?, C.J.F. Williams, Oxford University Press, 1981
See also
External links
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