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
- Hobbes's 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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René 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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Descartes's 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 God's 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 God's 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 mind's 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 God's Existence
- What I clearly and distinctly perceive to belong to a thing really does
- I clearly and distinctly perceive that God's nature is that of a supremely perfect being
- It belongs to the nature of a supremely perfect being to exist always
- 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 God's properties without God's existing
- But to reason this way is fallacious: it is existence itself that cannot be separated from God's nature as a perfect being
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Knowing God's Nature
- God's 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 God's 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 else--a 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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Naïve Beliefs About Sense
- Bodies--my own and others--seem 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
- My passive faculty of sensing requires an active faculty producing what is sensed
- This faculty requires no act of understanding and it operates against my will
- So, the active faculty is not in me
- So, the active faculty is in another substance: God, a super-human spirit, or body
- If it were not in body, God would be a deceiver
- God is no deceiver
- 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 reaming
- Waking life is connected without interruption, while dreaming life is not
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