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What is Metaphysics? • What is Real? • Metaphysics, inquires, presupposes some theory of what is real, and of what exists? • Metaphysics is closely related to Epistemology; in the same way that Epistemology asks, What is Knowledge and how does it differ from opinion/belief? Metaphysics asks, What is Reality and how it differs from mere appearance? • What is Reality and what are the standards or criteria for what count as REAL? • Both Eastern and Western Traditions have similar definitions of REALITY, that is what is PERMANENT, UNCHANGING, and UNCAUSED can be real. • Reality then can consist of Matter – Materialism- Physical Objects are real, due to the evidence gather from the senses and perceptions. It insists that matter alone provides a sufficient explanation of reality;understanding its physical processes id sufficient. • Reality then can consist of Ideas –Idealism- Thoughts, concepts, minds are real, due to the a priori notions of the mind. • Reality then can consist of both Matter and IdeasDualism, material and immaterial exists- body and mindbut how does one explain the relation between the two due to their different nature? • Pragmatism: Unlike Plato and Aristotle, who were concerned with how things actually are, pragmatists do not care what something is really like; what they do care about is how something works. The ordinary position regarding the existence of PHYSICAL OBJECTS: • Objects Exists, because we the senses can perceive them. Why is an object existent: i.e. and object in the garden. – It persists over time, its existence is not only temporary – The object is conceivable by sight and touch by many observers – It occupies space – It is capable of motion – It has shape and size – The object does not depend for its existence on the mind of an observer – We could apply the same principles to any object in the universe, the car in the parking lot, etc • This position is called NAÏVE Realism • Metaphysics, does not present arguments to proof that Objects do not exist, but it is possible, it could be, that we are mistaken about their existence? Arguments against NAÏVE Realism: • 1.Direct Perception: – Physical Objects are known through visual illusion- is seeing as it is, is seeing as it is not. – Examples, a stick half immerse in water- straight and bent – A penny- from side appears elliptical, vertically is round, horizontally a straight line. • 2.Casual Argument: – The pen looks gray to me, because the light of a certain wave length is being transmitted – brain, impulses, – If my eyes had been focused differently then everything would appear double – What is present in the visual field of an observer depends in the conditions of illumination, structure of eyes, nervous system – Color, or a carpet, pants- things do not change color, looks double color Distinction between sense data and physical objects – Sense data are not qualities of physical objects nor part of physical objects – how can we claim that physical object exist? – Senses: Sight, touch, sound, smells, taste (ACCIDENTS) it is SENSE DATA- QUALITIES OF OBJECTS NOT PART OF PHYSICAL OBJECTS – OBJECT: Red Ball, there has to be something, ball, apple, to be red. – Is something, capable of independent existence? Revised, 11/6/03 René Descartes (1596-1650 AD) Meditations on First Philosophy (1641) (Text, pp. 283-306) Anthem Background Descartes’ Problem • The problem of skepticism (D concentrates on 2 types of skepticism) – General skepticism: There are NO indubitable beliefs or propositions. – Skepticism concerning the existence & nature of the “external world”: The existence and nature of the “external world” cannot be known. D’s program of radical doubt • Treat any belief that is to the slightest extent uncertain & subject to doubt just as though it is obviously false. • Accept only those beliefs that are completely certain and indubitable. • Work on the foundations of my beliefs. Foundational Beliefs • Empiricism: True beliefs are acquired through sense experience. • My beliefs are not products of insanity. • My beliefs are not products of my dreams. Foundational Beliefs, cont’d • Physical objects: Even if we fail to perceive physical objects accurately, the “primary [measurable] qualities” of such objects (matter, extension, shape, quantity, size, location, time, etc.) are really real (i.e., physical objects do really exist). • Even if empirical beliefs are subject to doubt, mathematical propositions are indubitable (e.g., 3 + 2 = 5, a square has neither more nor less than four sides). Meditation II Descartes’ Refutation of Radical Skepticism Descartes’ refutation of radical skepticism “Cogito ergo sum!” What does this mean? The most famous statement in the history of philosophy: “I think; therefore I am.” Discourse on Method (1637) “If I am deceived, then I must exist!” I cannot doubt the truth of the statement, “I exist.” Thus, Radical (general) skepticism is refuted. Meditation II, cont’d The Mind-Body Problem & Descartes’ Psycho-Somatic Dualism Three metaphysical perspectives relevant to the “mind-body problem” Metaphysical Dualism: Reality is twodimensional, partly material and partly nonmaterial (minds, ideas, souls, spirits, consciousness, etc.). Metaphysical Materialism: Reality is nothing but matter-in-motion-in-space-and-in-time. There are no non-material realities. Metaphysical Idealism: Reality is nothing but Mind, Idea, Soul, Spirit, Consciousness, etc. Matter does not exist (it’s an illusion?). Application to the “mind-body problem” • Metaphysical Materialism: A person is nothing but a physical organism (body only). • Metaphysical Idealism: A person is “consciousness only” (mind, soul, spirit); not at all a material being. • Metaphysical Dualism: A person is a composite of (1) “mind” (consciousness, soul, spirit) and (2) body. Cartesian Dualism • I know with certainty THAT “I” exist (Cogito ergo sum), but • WHAT am “I”? • Am “I” my body? No, because I can doubt the existence of my body, whereas I cannot doubt the existence of myself (the “I”). • “I” am a thinking thing, a thing that doubts, understands, affirms, denies, wills, refuses, imagines, and has sensations. Can you doubt the existence Is Descartes right? of your body (as well as other physical things)? Why or why not? “I can conceive of myself as existing without a body, but I cannot conceive of myself as existing without conscious awareness.” Bryan Magee, The Great Philosophers (Oxford 1987) Descartes’ mind-body dualism leads to . . . . Meditation III, which deals with (1) skepticism concerning the existence & nature of the “external world” & (2) the existence of God God & the removal of doubt as to the existence of the external world The content of Meditation V • Mathematical thinking & its (physical & non-physical) objects: clarity & distinctness again -- what is clear & distinct must be true • D’s “ontological” argument for the existence of God • God & certainty for the existence of God Descartes’ third argument (the ontological argument again) 1. If the nonexistence of God (an infinitely perfect being) were possible, then existence would not be part of God’s essence (that is, existence would not be a property of the divine nature). 2. If existence were not part of God’s essence (that is, a property of the divine nature), then God would be a contingent (rather than necessary) being. 3. The idea of God as a contingent being (that is, the idea of an infinitely perfect being with contingent rather than necessary existence) is self-contradictory. 4. It is impossible to think of God as not existing. 5. The nonexistence of God is impossible. Certainty about God is the basis of certainty about everything else. Meditation VI Removal of doubt as to the existence of the external world • • • • Since God exists & is no deceiver, it follows necessarily that the external world can be known to exist. Gilbert Ryle: “Descartes’ Myth” Ryle Concept of Mind (1949) The “official doctrine,” hailing chiefly from Descartes, is substance dualism. (1900-1976) Bifurcation of mental/physical & ‘inner’/‘outer’; assumption that there are two kinds of existence/status; etc. Ryle This dogma of the “Ghost in the Machine” is entirely false, and “false not in detail but in principle.” “It is one big mistake and a mistake of a special kind. It is, namely, a category mistake.” Ryle This dogma of the “Ghost in the Machine” is entirely false, and “false not in detail but in principle.” “It is one big mistake and a mistake of a special kind. It is, namely, a category mistake.” Ryle Examples: ‘university,’ ‘division,’ ‘team-spirit,’ ‘average taxpayer.’ “so long as John Doe continues to think of the Average Taxpayer as a fellow-citizen, he will tend to think of him as an elusive insubstantial man, a ghost who is everywhere yet nowhere.” Ryle Assumption that ‘mind’ belongs to the categories of mechanics: ‘thing,’ ‘stuff,’ ‘cause,’ etc. But, according to the official doctrine, mind has to be a non-physical, non-mechanical thing/stuff/cause; and it cannot be governed by mechanical laws. Ryle Descartes is wrong to think that our outward actions or behavior is evidence for an inner state that causes our behavior. Using psychological predicates to refer to mental objects is a category mistake. Ryle For example, according to dualism, attentive listening would be two acts. Firstly the physical process of receiving sound, and secondly, the mental process of ‘attending’ which causes our listening to be attentive. Ryle But a person is not listening as a physical action and being attentive by a mental action. There is merely one process characterized as ‘attentive listening.’ Take boiling water. The boiling is not actually some hidden ‘object’ which is a separate thing from the water. Boiling is simply the behavior of the water, not a part of it, as ‘attentive’ is merely the behavior of the subject. Ryle Thus, the mind is not a non-physical substance residing in the body, “a ghost in a machine,” but a set of capacities and abilities belonging to the body. According to Ryle, all references to the mental must be understood, at least theoretically, in terms of witnessable activities. (psychological behaviorism) Ryle Criticisms of Ryle’s psychological behaviorism: - Not all mental states are shown in behavior; - Inadequate when applied to yourself; - Behavior is not indicative of mental states but the other way around; - Doesn’t account for qualia.