“Meditations on First Philosophy”Meditations 1-6
René Descartes
Lived 1596-1650
Often described as the “father of modern philosophy.” Modern philosophy is distinguished by its focus on reason, rather than religion or tradition, as the primary mechanism for understanding the world.
Well known as a mathematician Descartes is credited with the invention of analytic geometry, and is the namesake of the Cartesian coordinate system.
The Rationalist❖ A combination of factors, including Luther’s Protestant Reformation
and Copernicus’ advances in scientific understanding and technique, led to the erosion of the hierarchical, authoritarian medical worldview and weakened the authority of Scholastic philosophy, which relied heavily on Aristotle.
❖ Rene Descartes’ scientific and mathematical interests demanded observable, provable evidence of a nature lacking in cumbersome reliance on authority of Scholasticism, and resulted in a radical proposal:
❖ Start fresh; throw out everything we think we know and build a system based entirely on ideas whose truth can be clearly and distinctly known to us firsthand.
Rationalist vs Empiricism❖ Rationalists claim that there are significant ways in
which our concepts and knowledge are gained independently of sense experience.
❖ Descartes
❖ Empiricists claim that sense experience is the ultimate source of all our concepts and knowledge.
❖ Locke, Hume and Berkeley
General Cogito (existence of the �I�)
(Med. I) (Med. II)
Mind-Body Dualism
Skepticism
God (no deceiver)
External 1. My idea of God (III)
World 2. My contingent
(Meds. III-VI) existence (III)
3. The ontological
argument (again) (V)
The Meditations as a Whole
An Unsatisfactory World of Uncertainties
A better world“World of truths”
Finding a bedrock(Something one cannot doubt)
The descent
into doubt
truth finding for procedureA
Methodic doubt
❖ Methodic doubt is a form of skepticism that rejects any idea that could possibly be false, no matter how remote that possibility.
Descartes’ Meditations❖ Descartes notices that many of his beliefs are unjustified
and/or uncertain.
❖ These include beliefs about the external world and the mind
❖ He’s interested in determining which, if any of his beliefs, are certain. By doing this, he thinks, he can establish a foundation for the rest of his beliefs.
❖ This approach to knowledge is called foundationalism.
Descartes’ Meditations❖ Foundational pieces of knowledge are distinct from other kinds
of knowledge.
❖ They require no justification.
❖ You might call them the end of the chain of explanation.
❖ The foundationalist thinks that once foundational pieces of knowledge are discovered, the rest of what we know can be inferred from these foundational pieces of knowledge.
❖ Why would anyone think that there are pieces of knowledge that require no justification?
Descartes’ Meditations
❖ How might we discover the foundations of our knowledge?
❖ “I will apply myself earnestly and unreservedly to [the] general demolition of my opinions.”
❖ Descartes proposes to withhold belief from (i.e. doubt) any claim about which he is not absolutely certain.
❖ What does it mean to be certain?
Cartesian Certainty❖ Descartes has a strong criterion for certainty.
❖ A belief is not certain merely when it is unreasonable to doubt, but when it is impossible to doubt.
❖ He aims, then, to undermine the certainty of most of his beliefs by asking if it is possible to doubt them.
❖ He doesn’t have to examine each of his beliefs individually; he goes after the foundations of his Beliefs.
FIRST VICTIM Beliefs acquired by the senses
❖ Are we sure about the things we see when we’re far away from them?
❖ Are we sure about the things we see and touch when we’re close to them? Am I sure, for example, that I’m really seeing my own hands in front of my face?
❖ No! We’re often deceived about this when we sleep
Descartes’ Response Dream Argument
❖ I have dreamed that x when x was false.
❖ If I cannot distinguish an experience from a non-truthful experience, then I am not justified in regarding it as truthful.
❖ Waking experience that x is truth only if I can distinguish it from my dream experience.
❖ I cannot find any such distinguishing mark.
❖ ———————————————————————————-
❖ I am not justified in regarding my present waking experience x is truth.
SECOND VICTIM Beliefs about mathematical/logical relationships
❖ Dream skepticism isn’t enough to undermine these beliefs, because even when we’re dreaming, 2+2=4.
❖ To undermine these beliefs, we’d need a deeper kind of skepticism
The Evil Demon
❖ P1: If I cannot be certain that I’m not being deceived by the an Evil Demon (or the matrix), then I can’t be certain that 2+2=4 (or that I have hands!)
❖ P2: I cannot be certain that I’m not being deceived by an Evil Demon (or the matrix).
❖ C: I cannot be certain that 2+2=4 (or that I have hands!)
❖ DOES ANYTHING SURVIVE?
Second Mediation
“The Cogito” Cogito, ergo sum
❖ “After everything has been most carefully weighed, it must finally be established that this pronouncement “I am, I exist” is necessarily true every time I utter it or conceive it in my mind.”
❖ The one thing I cannot doubt is my very existence. After all, I’m doubting, right?
An evil demon may be making me believe
things that are false.
There is nothingof which I can
be certain.
But when I say “I am; I exist”, I cannot be wrong
about this.
An evil demon couldtry to make me believe this
only if I really do exist.
I am thinking, therefore I exist.
What is the “I” that does exist?
❖ https://www.youtube.com/watch?v=7iGjiSbEp9c
Wax Argument❖ What are the essential properties of
an ordinary physical object, say, a piece of wax?
❖ Descartes wants to say that we cannot know what wax is through our senses.
❖ The argument was created in order to analyze what properties are essential for bodies, show how uncertain our knowledge of the world is compared to our knowledge of our minds, and argue for rationalism.
When the wax is exposed to heat, the characteristics change.
The wax Initially perceived:
The wax as later perceived: Sense:
sweetness of honey tasteless taste
odor of flowers odorless smell
colored altered Color sight
has definite figure not the same figure sight/touch
has definite size bigger sight/touch
hard liquid touch
cold warm touch
easily handled not easily handled touch
emits sound when hit no sound when hit hearing
❖ The senses tell us that the wax is yellow, that it is cool to the touch, that it has a certain shape, that it smells like flowers and tastes like honey.
❖ However, when we bring the wax close to a fire, all these sensuous properties change: it becomes clear, hot and loses its shape, smell, and taste.
❖ So, Descartes concludes that none of these sensory properties belong essentially to that piece of wax. instead, the only arise as it interacts with our sensory organs.
❖ What belongs to the wax itself?
❖ Descartes concludes that what must belong to a material object like the wax is simply that it persists in time and space (that it is extended).
❖ Descartes thinks that we’ve arrived at these conclusions by stripping the wax of all the properties we perceived it to have.
❖ What is left is what we “grasp” of the wax, not through the senses, but rather through our intellectual faculties.
Problem The Cogito doesn’t really help us all that much
❖ How do I get from the knowledge that I exist to any kind of knowledge about what kind of a thing I am?
❖ Descartes’ answer: God
Why does Descartes say this?
“I must, as soon as possible, try to determine (1) whether or not God exists and (2) whether
or not He can be a deceiver. Until I know these two things, I will never be certain of anything
else”
❖ I have an idea of a being that is “perfect” (this being is all-powerful, all-knowing, all-good.
❖ This idea is perfect “in my mind.”
❖ But nothing that is greater could have come from anything that is lesser.
❖ So this idea must have come from an actually existing perfect being.
❖ Ideas can come from oneself (innate), other ideas or experience.
❖ I am not sufficiently perfect.
❖ None of my other ideas are sufficiently perfect.
❖ So this idea must have come to me from some being, who is all-powerful, all-knowing, all-good.
Conclusion of the 3rd Meditation
"From the simple fact that I exist and that I have in my mind the idea of a supremely perfect being, that is, God, it necessarily follows that God exists . . . . The whole argument rests on my realization that it would be impossible for me to exist as I do -- namely, with the idea of God in my mind -- if God didn’t exist. It also follows that [since God is perfect] God cannot be a deceiver [because fraud and deception are caused by defects] . . . ."
Meditation IV
And why does Descartes think it necessary to prove the existence of God?
❖ It's because he's looking for a guarantee that the "external world" (the world outside of his mind) is really real and not just an illusion.
❖ How does a proof of the existence of God help him with that problem?
❖ The point is that God (who is no deceiver) guarantees that the world I perceive through my senses is really there. God authenticates my sensory experiences, thus making sensation generally reliable, not in and of itself, but because God (being perfectly good) will not allow me to be systematically deluded and deceived.
❖ By the way, if Descartes trusted his senses, this "external world" issue would not be a problem for him. But Descartes, a "Rationalist" rather than an "Empiricist," does not trust sense experience. He needs something more than sense experience to convince him that the "external world" is real. He needs God.
The Basic Thrust of Meditation IV:❖ If God is no deceiver, how is human error with respect to truth and falsity possible, and
how is that error to be explained?
❖ Human nature is equipped with an intellect (faculty of knowing) and a free will (faculty of choosing), which interact in the pursuit of truth. The intellect is capable of forming beliefs that can't be doubted and therefore are certainly true. However, the intellect can also consider claims that are subject to doubt and that therefore may be false. The human will is free to affirm or deny propositions proposed to it by the intellect. Error results when the will (1) denies the truth, or (2) affirms claims that are false, or (3) asserts knowledge where there is doubt.
❖ Error is avoidable where a person limits her his affirmations and denials to "those matters that are clearly and distinctly [indubitably] shown to . . . [the will] by the intellect . . . . " and remains (more or less) neutral with respect to all claims that are subject to doubt.
❖ Why does God permit human error? If human nature were created both free and incapable of error, it would be more perfect than it now is; but it may be that the apparent imperfection of human nature in this respect is necessary to "a greater perfection of the universe as a whole."
Meditation 4“What then, is the source of my errors?
They are owing simply to the fact that, sincethe will extends further than the intellect, I
do not contain the will within the same boundaries;rather I also extend it to things I do not understand.
Intellect Will
Intellect Will
“If I hold off from making judgement when Ido not perceive what is true with sufficientclarity and distinctness, it is clear that I am
acting properly and i am not committing an error.But if I instead were to make an assertion or a denial,
then I am not using my freedom properly.”
Clear and distinct ideas Error
The content of Meditation V
❖ Mathematical thinking & its (physical & non-physical) objects: clarity & distinctness again -- what is clear & distinct must be true
❖ Descartes’ “ontological” argument for the existence of God
❖ God and certainty
Descartes’ third argument…
❖ for the existence of God
❖ 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.
❖ A God that lacks existence would not be a perfect being.
❖ A more perfect being is conceivable, namely one that has all the same attributes, as well as the attribute of existence.
❖ God without existence is like a triangle without internal angles equally 180 degree and three sided.
❖ A God that lacks existence is less perfect, than one that does exist.
What do the internal angles of this triangle equal?
How many sides does this triangle have?
Our idea of God is that of all-knowing, all-powerful and all-good.
Perfect
Which would you consider to be more perfect?
To exist Not to exist
Meditation VIRemoval of doubt as to the existence of the external world
❖ Since God exists
❖ And is no deceiver,
❖ it follows necessarily
❖ that the external world can be known to exist.
❖ WHY?
Something must cause the idea of a triangle.
Descartes was inclined to believe that things, which resemble those perceptions,
created the sensory perceptions.
Something must cause the idea of a triangle.
Descartes was inclined to believe that things, which resemble those perceptions,
created the sensory perceptions.
Descartes would be deceived if the perceptions were caused by some other means.
Since, God is not a deceiver, God would not have misled Descartes
into thinking there are material objects if there were not.
So, he concludes that material objects exist.
