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Meditations on First Philosophy Philosophy 1 Spring, 2002 G. J. Mattey

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The Religious Crisis The Protestant Reformation destroyed the universal intellectual authority of the Roman Catholic Church Individual conscience was offered as a higher authority One philosophical issue was how to adjudicate this dispute Another was what role reason should play

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The Scientific Crisis Natural philosophers such as Galileo challenged the Aristotelian account of the natural world Mathematical explanations appeared preferable to teleological explanations Hobbess account of the natural world seemed to exclude any role for God

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The Skeptical Crisis The writings of the ancient skeptics had been recovered during the Renaissance Powerful skeptical arguments were mobilized by philosophers such as Montaigne These arguments threatened religious as well as scientific belief

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The Problem of the Criterion This problem was posed by ancient Pyrrhonian skeptics How can a dispute (e.g., authority vs. conscience) be settled? One may not appeal to what is in dispute So a new criterion is needed If the new criterion is in dispute, the problem arises once again

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Ren Descartes Born 1596 French Studied under the Jesuits Invented analytic geometry Pursued many scientific investigations Father of modern philosophy Died 1650

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Descartess Contributions Produced a comprehensive mathematical system of the world, with laws of nature such as inertia Looked for new first principles of philosophy in pure reason Tried to refute skepticism decisively Attempted to prove that the mind an autonomous being, distinct from the body

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Preconceptions The Aristotelian account of knowledge began with notions acquired from sense- perception Descartes held that these preconceptions acquired in youth are the source of error He sought to overturn the preconceptions of his youth, thus purging his mind of error

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The Method of Doubt Descartes sought a method of removing all at once his erroneous opinions He would treat as false any opinion that was open to the slightest doubt Once all dubious opinions were removed, he would see what survived He would build on this foundation an edifice of knowledge free of preconceptions

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Doubts About Specific Objects My opinions about specific objects are based on sense-perception Opinions about obscure objects (e.g., small or distant ones) are dubious because I am often deceived by our sensory input Opinions about near and familiar objects (e.g., I am seated next to the fireplace) are dubious because I have no criterion for distinguishing my waking states from my dreaming states

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Doubts About General Objects My mistaken opinions about specific objects depend on my opinions about general objects (e.g., shapes) People make errors regarding even the simplest things (e.g., that 2+3=5) I may have been made so that I can be deceived even about them A powerful God could have brought it about that the natural universe does not exist A lesser cause or chance could easily have brought it about that I am defective

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Sustaining Doubt The method of doubt requires that for now I treat my opinions about sensed specific and rationally known general objects as false A uniform way of keeping my doubts in mind is by assuming that there is a powerful evil genius who is exerting its will to deceive me Still, it is difficult to sustain this doubt due to laziness

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If I Am Thinking, I Exist Is there anything left that is not subject to doubt? Perhaps it is some specific object that is not perceived through the senses Such an object is myself, since I must exist in order to doubt at all (Augustine) In the period of time when I think (cogito) I am something, an evil genius cannot bring it about that I am nothing

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I Am a Thinking Thing What is the I which, necessarily, exists when it is thinking? It is a thinking thing (res cogitans) It need not have any bodily characteristics, since it has been assumed that there are no bodies and no knowledge of general things So what I am is not known by imagination, which simulates shapes

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What a Thinking Thing Does Most characteristics of a thinking thing are conditions that allowed me to reject my former opinions Doubting Understanding Affirming Denying Willing Refusing

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Imagining and Sensing The same thing that doubts, understands, etc. also: Imagines many things, even when not willing to do so Notices many things that appear to arise from the senses It imagines things as if bodies exist It senses, i.e., seems to see, hear, feel, etc. I cannot doubt that these are powers in me They can all be classified as thinking

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Intellectual Perception Suppose that bodies exist: how could they be known? The senses reveal nothing constant in them The imagination cannot comprehend their infinite possible variations They are perceived only through inspection by the intellect, which understands their constant features: extension, flexibility, mutability The intellectual inspection that reveals the nature of bodies even more clearly reveals the nature of mind

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Clear and Distinct Perception I now know a number of things about myself To know these things, I must know what it is for me to know them The condition for knowledge is clarity and distinctness in the perception of what I affirm It seems a general rule that whatever I perceive very clearly and very distinctly is true

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The Return of Doubt When I turn my attention to what I perceive very clearly and distinctly, I believe that I cannot be deceived about them But when I turn my attention to my preconceived notion of God, I believe that I might have been made so that I can be deceived about them To dispel this very tenuous and, so to speak, metaphysical doubt, it must be determined whether God exists and can be a deceiver

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Truth and Falsity Truth and falsity reside in judgments Judgment embraces in thought something beyond the subject judged The primary subjects of judgment are ideas Ideas in themselves are neither true nor false (nor are acts of will) Error arises most commonly when the idea is taken to be a likeness of something outside me

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Grounds for Judgment Why do I take it that my ideas are likenesses of things outside me? I seem to have been taught so by nature: I spontaneously believe this Natural impulses can give rise to error But the light of nature always yields true judgments (e.g., from the fact that I doubt, it follows that I am) The ideas come to me against my will But they might be produced by something in me Even if the ideas come from things outside me, they might not be likeness of them (e.g., the small image of the sun)

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A Hierarchy of Ideas Ideas as modes of thought are equal: one idea is no more an idea than another But they are not equal in the objects they represent An idea of a substance has more objective reality than that of an accident An idea of an infinite substance has more objective reality than that of a finite substance

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Cause and Effect We know by the light of nature that the efficient cause of a thing has at least as much reality as its effect This holds for objective reality as well as the formal reality of existing things The cause of the objective reality of an idea must have at least as much reality as it does: it cannot get this reality from nothing

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The Cause of Ideas There must be a formal reality which is the cause of the objective reality of ideas This formal reality might be an idea itself But the causal chain cannot be infinite: there must be a non-idea causing the first idea This is a sort of archetype that contains formally all the reality that is in the idea merely objectively

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Escape from the Circle of Ideas? Suppose there is an idea in me whose objective reality is so great that I cannot be the formal reality that is its cause Then I am not alone in the world: the cause of that idea exists as well Are there any ideas of this sort? Different classes of ideas will have to be examined

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Ideas of Finite Beings I could be the cause of ideas of other men, animals or angels: they are like me And I could be the cause of ideas of physical objects Their sensory qualities are very obscure, and even if accurate, they are no more real than I Their greatest objective reality is as substances, but I am a substance as well

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The Idea of God God is an infinite, independent, supremely intelligent and supremely powerful substance who created me and all else The idea of God is not materially false, like that of heat or cold, because of its clarity and distinctness I do not have the degree of reality needed to produce an idea of God There is much in me that is merely potential and not actual

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The Cause of Myself Since it is easy to be blinded by preconceptions, I will ask whether I could exist without God I did not get my being from myself, since I would have given myself all the perfections I have not always existed, since I need something to sustain my existence over each moment of time, and I cannot perpetuate my own existence I did not get my being from my parents, since they could not be the ultimate source of my idea of God

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The Existence of God The only way I can have an idea of God is by Gods causing me to have the idea Since I and my idea exist, God exists The idea of God in my mind is like a signature on a painting The idea I have of God precludes Gods being a deceiver, since deception implies an imperfection

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The Possibility of Error God did not give me a faculty of judgment that would lead me to error if I did not use it properly So error is the result of my improper use of my judgment This is possible because of my finitude, the fact that I partake to some extent of nothing

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The Cause of Error Why do I err, since it seems that it would be better for me not to? I cannot know what is best based on what appears to my mind Error is the result of my faculty of choosing over- reaching my faculty of knowing Will is infinite, but my understanding is limited I resemble God most through the infinitude of my will

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Willing Willing is to be able to do or not to do the same thing, e.g., to affirm or deny it A better account: willing is the minds movement toward or away from what is proposed by the intellect, in a way that we sense we are determined by no external force

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Freedom of the Will Freedom is the inclination to choose the course that appears to be good and true This inclination may be based on clear understanding or an impulse implanted in me by God In my judgment that I truly exist, a great light gave way to a great inclination of my will Therefore, indifference is the lowest degree of freedom, since the intellect sees no reason to prefer one course to another

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Using and Abusing Free Will The indifference of the will extends to that about which we know nothing It even extends to what is probable My knowledge that it is not certain (e.g., whether I have a body) pushes me away from judging it as true This diffidence is a proper use of judgment But making an assertion or denial in such a case is abuse of my free will If I am right, it is only through luck

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No Complaints Against God The ability to err might be thought to be grounds for complaint against God, but: I should thank God for my limited intellect, since God owes me nothing My will must be unlimited (and hence subject to error) because it is unitary Error is privation, and hence not a thing Even though God could have made me error-free, it was for the best that I was made as I was I can still avoid error through self-restraint

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So Do External Things Exist? Some remaining issues about the nature of God and myself will be postponed The main question is whether the doubts about the existence of external objects can be overcome? The first step is to examine the ideas of external things for clarity and distinctness This will reveal what they must be

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Extension and Duration I have clear ideas of two continuous quantities, extension and duration Shapes and positions are understood through extension, and motion through extension and duration They apply to true and immutable natures, whether or not external objects exist

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Knowledge of Natures Natures are not fabricated by me, as can be seen through geometrical demonstrations I cannot refrain from assenting to judgments about them while perceiving them clearly Even when my attention was on the senses, I still regarded mathematical demonstration as certain

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Another Proof of Gods Existence 1.What I clearly and distinctly perceive to belong to a thing really does 2.I clearly and distinctly perceive that Gods nature is that of a supremely perfect being 3.It belongs to the nature of a supremely perfect being to exist always 4.So, God always exists

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A Sophism? We do not suppose that because a mountain is inseparable from a valley, a mountain exists: they may both fail to exist So it seems possible to think of all Gods properties without Gods existing But to reason this way is fallacious: it is existence itself that cannot be separated from Gods nature as a perfect being

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Knowing Gods Nature Gods nature, like that of a geometrical object, is not fabricated by me God is the only being I can think of whose essence includes its existence When I see that God now exists, I also perceived clearly that God has existed eternally There are other features in God that I perceive and cannot remove or change

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The Most Certain Knowledge The main way in which we can tell that we know Gods nature is through the clarity and distinctness of the perception of it This is revealed even if it was obscured initially by prejudice. Once it is known, nothing is more certain, or known more easily than that God exists

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Removing a Slight Doubt The remaining tenuous doubt was about things which are no longer clearly perceived God is not a deceiver, so if I remember that I had clearly perceived them, I can count on my memory Errors in memory occur when the original perception was not clear This holds even if I am always dreaming

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Imagination It seems that it follows from my use of the imagination that material objects exist Use of the imagination requires more exertion than that of the pure intellect I could exist as a pure understanding even without imagination So a probable conjecture is that imagination depends on something elsea body

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Sense Some things are better known through sense than through the intellect These include colors, sounds, tastes, pains Can an argument for the existence of material things be based on the contributions of the mode of thinking called sense? I must rehearse what caused doubt initially

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Nave Beliefs About Sense Bodiesmy own and othersseem to be the objects of sense Associated with my body are ideas of pain and pleasure Many other ideas are also associated with bodies They come to me against my will, and so do not seem to come from me My body seems particularly related to me

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Doubts About Bodies There are numerous perceptual illusions, even with respect to pain I have no reason to believe that ideas in my dreams come from bodies, but I can dream anything I think I receive from bodies I might be constituted by nature to be deceived about what is true What is against my will could originate in me

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Separating Mind from Body God can make me without a body So my essence consists entirely of my being a thinking thing I am really distinct from my body Imagination and sense depend on my mind as modes But I can exist without them

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Bodies Exist 1.My passive faculty of sensing requires an active faculty producing what is sensed 2.This faculty requires no act of understanding and it operates against my will 3.So, the active faculty is not in me 4.So, the active faculty is in another substance: God, a super-human spirit, or body 5.If it were not in body, God would be a deceiver 6.God is no deceiver 7.So, bodies exist

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The Teachings of Nature Nature is the handiwork of God It teaches me about the relation of my mind and my body I and my body form a single intermingled thing It also teaches me which other bodies should be pursued or shunned Anything else belongs exclusively to mind or to body Nature does not teach me that there is a likeness between ideas and bodies

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A Final Problem God, through nature, teaches me what to avoid as harmful or pursue as useful I am sometimes mistaken in this, yet God is no deceiver Attention to what is clear and distinct does not solve the problem, because in matters of utility, everything is obscure and confused

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Natural Errors The mind is a simple thing, while the body is a composite with many parts The interface of mind and body is in a common sense in the brain What is communicated to the mind is the last motion reaching the common sense But the motion from a remote part of the body could be corrupted on the way

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Coherence The final doubts have been dispelled A new argument against the dream hypothesis is given One can notice a considerable difference between waking and dreaming Waking life is connected without interruption, while dreaming life is not