intuition and deduction thesis content Flashcards
what is a rationalist
- descartes
- concerned with reason shaping our knowledge
what is deduction
- DRAWING CONCLUSIONS that follow from premises
- cannot be doubted as it is reached following a valid argument with true premises
what is rational intuition
- how EASILY someone is able to GRASP A CONCEPT
- the intellectual capacity to grasp the truth of a preposition directly
what are clear and distinct ideas and give examples
CLEAR = vivid and immediatly accessible to the mind, known with certainty, cannot be doubted = pain
DISTINCT = can be distinguished from other ideas, cannot be confused with other ideas = pain is not always distinct but is clear, sometimes we cannot easily identify the source of our pain
- a priori truths, mathematical truths
what role do clear and distinct truths play in descartes philosophy
- Descartes aim is to reach certain knowledge which is clear and distinct
- in order to do this he doubts everything he claims to know
- he rationally intuits several clear and distinct ideas
—> e.g the cogito - he later goes on to reach clear and distinct ideas of God, Matter and Mind
define philisophical scepticism
the claim that one or more of our usual justifications for claiming our beliefs are inadequate so we dont have knowledge
define local and global scepticism
local = doubting one particular part of knowledge —> doubting moral properties, other minds, Gods existance
global = doubting all domains of knowledge or truths —> doubting existance of the external world, brain in a vat, evil demon
what is certain knowledge and why is descartes concerned about finding it
- knowledge which cannot be doubted
- descartes is concerned about finding this so he can provide a definite foundation for our knowledge in general
what is infallibilism
- descartes defines knowledge as a true belief justified beyond doubt just as infallibilism defines knowledge
- basically anything which cannot be doubted at all counts as knowledge
- this would rule out sense perception but descartes aims to fix that
what are descartes three waves of doubt
- sense deception
- dreaming
- evil demon
summarise descartes first wave of doubt - sense deception
what type of scepticism is this
- at times our senses decieve us
- objects can appeaar different to what they truely are —> illusions, hallucinations, PV
- our 5 senses cannot be trusted fully as they can change our perceptions
- since descartes cannot be certain about the information provided through our senses, they cannot be a source of knowledge
- so the information from our senses is unreliable but not wrong
- LOCAL
why is descartes first wave of doubt (sense deception) not sufficient to call into doubt all of our knowledge
- only a prosteriori knwoledge can be doubted in this wave —> however this relies of specific instances of sense deception not SD as a whole
- a priori truths such as mathematical ones cannot be disproved through SD
summarise descartes second wave of doubt (dreaming)
what type of scepticism is this
- at any given moment we could be dreaming
- could be dreaming such a realistic dream that we cannot tell the difference
- local
why is descartes second wave (dreaming) not sufficiant into calling into doubt all of our knowledge
- does doubt all a prosteriori truths as they come from sense perception
- DOES NOT DOUBT A PRIORI TRUTHS
what are descartes two reasons as to why we dont exist in a dream
- reality is more clear and coherent than dreams —> we can easily tell the difference
- the only reason we can dream is because there is a reality to base those dreams on (think Humes copy principle) and to return to
summarise descartes third wave of doubt (the evil demon)
what type of scepticism is this?
- unless we can prove the existance of God, an evil demon may be convincing and tricking us about every thought we are having - a priori or a prosteriori
- the demon would be able to trick our senses and minds
- the problem is we wouldnt be able to tell if we are being tricked or not —> we wouldnt know either way because our senses would be the same
- global scepticism
why is descartes third wave if doubt (the evil demon) enough to call into doubt all of our knowledge
- the issue is not that the evil demon exists, rather we cannot prove that it doesnt exist
- it undermines all our knowledge claims because we cannot know for certain that we are experiencing those perceptions
- cannot be certain of anything —> a priori or a prosteriori
what is descartes response to the evil demon
- rationally intuiting —> deducing —> cogito —> God exists —> evil demon does not exist —> existance of the external world
what is descartes cogito an example of
a priori intuition
- by doubting the exitance of everything, he rationally intuits that doubt cannot be doubted so “i think therefore i am”
- this is a clear and distinct idea
what was humes copy principle
- all ideas can be traced back to experience
- ideas = formulations of simple ideas —> copies of impressions derived from sense experience
- he says we can trace ideas of God, causation and logical laws back to experience
how does hume use the copy principle to argue there is no such thing as the self and how does this undermine descartes rational intution of the cogito
- we have impressions of ourselves which are isolated from all perception/thought
- if there is no experience of a distinct “I” from our perceptions and thoughts then we arent justified in claiming that such an “I” exists
- Hume claims that the “I” is just a bundle of qualities/perceptions/thoughts not one distinct mind which thinks and exists
how might descartes respond to hume claiming there is no such thing as the self
- thoughts require a thinker
- hume defined the mind as an activity but there has to be something that is doing that activity
what is begging the question and how may descartes be accused of this
- logical fallacy
- assumes the existamce of … in first premise
- he needs to prove… without reffering to any sense of …
- a logical fallacy where someone assumes what they are trying to prove in the conclusion
- descartes assumes the existance of “I” in the first premise which he then goes on to prove in the conclusion
- he needs to prove the existance of “I” without reffering to any sense of “self”
how would descartes respond to being accused of begging the question in deducing the cogito
- he could give up his deduction of the cogito and just claim it is a rational intuition
- the rational intuition form of the argument is not open to being charged with begging the question because it isnt a deductive argument
- but this would mean it is a clear and distinct idea so then Humes copy principle could be used to disprove the cogito
what is the formal version of the trademark argument P1, P2, P3, C1, C2, P4, C3, C4
clear and distinct, ideas and cause, perfect, i cannot, so must come from, only God, idea mind, therefore
P1) I have a clear and distinct idea of an infinite and perfect God
P2) All ideas have a cause
P3) The effects cannot be greater or more perfect than the cause
C1) Therefore, i cannot be the cause of my idea of God as I am finite + imperfect
C2) Therefore, the idea of God must come from a perfect, infinite being
P4) Only God is infinite and perfect
C3) Only God can cause the idea of God in our minds
C4) Therefore, God must exist
Why is it important for Descrates to prove the existance of God
God is all perfect, all powerful, all loving, all loving so would make sure the evil demon doesnt exist which makes our perceptions reliable and proves the existance of the external world
what is humes fork
- a way of classifying what we consider prepositional knowledge - two classifications
1) relations of ideas, a priori, analytic
2) matters of fact, a prosteriori, contingent
if a proposition is not analytic or synthetic then it doesnt count as prepositional knowledge = “consigned to the flames” according to Humes = rendered meaningless
How can the existance of God be disproved by applying it to Humes fork about what counts as prepositional knowledge
- the proposition “God exists” is neither analytically nor synthetically true so it doesnt fit humes fork
- not a matter of fact because it is not true in nature of how the world is —> we cannot find empirical evidence for the existance of God
- not a relation of ideas because it isnt true by definition that God exists
- Therefore we cannot have knowledge about Gods existance so Descartes is wrong
How can Humes copy principle be applied to the existance of God
- NO INNATE IDEA of God, comes from experience
- we have impressions about the qualities of God - power, love, wise
- those simple ideas become complex ideas combined with the concept of infinity forming the idea of God
- so Descartes is wrong about there being an innate idea of God
what is Humes account of causation and how might this undermine Descartes trademark agrument thinks hume God arguement
causation= a-p..
we only know through observation that every cause has an
effect of a cause ccannot be…
constant conjunction
undermines P3
- Hume = we can only know causation to be a prosteriori
- we cannot know (without observing the world) that every cause has an effect let alone that the effect from a cause cannot be more perfect than the cause
- we have to demonstrate causual claims by reffering to experience
- causation = CONSTANT CONJUNCTION = we can infer it by observing repeated instances of A causing B
BUT we can NEVER BE CERTAIN about this because it is just an inferance - this UNDERMINES DESCARTES argument by disagreeing with P3 and claiming we would need repeated experiences of God causing this idea in our minds to infer a causual link
- we cannot have this, so cannot infer a causual link
Give the formal version of Descartes argument for proof of the external world P1), P2), P3), P4), P5), P6), C1), C2),
percieve a world, list three possible causes, if-then PE= voluntary, PE=, God then deceptive since caused by, cannot be deceptivve as God is-, external, MID
P1)I clearly and distinctly percieve a world of external objects
P2) The cause of this must be either my own mind, God, or external physical objects
P3) If the cause were my own mind, then those perceptual experiences would be voluntary
P4) Perceptual experiences are not voluntary
P5) If the cause were God, then those perceptual experiences would be deceptive (since i think they are caused by external objects, not God)
P6) However, those perceptual experiences cannot be deceptive as God exists and is all-good and not a deciever
C1) Therefore, those perceptual experiences must be caused by external physical objects
C2) Therefore, an external world of physical objects exists
The response to descartes proof of the external world is that is is circular - the Cartesian Circle
what is this?
- descartes= clear + distinct ideas = reliable but this relies on the existance of God to ensure that they are
- He uses his claim that his clear and distinct ideas are reliable to show that he has a clear and distinct idea of God which ensures he exists
- all circular
