Intuition and Deduction thesis Flashcards
What is intuition and deduction?
Intuition is the intellectual capasity to grasp the truth of a preposition (true or false statement) directly. A deductive argument is one where if the premises are true then the conclusion is garanteed to be true. Descartes uses intuition (basic facts) and deductive argument to produce garanteed truths using reasoning alone.
Descartes’ notion of clear and distinct ideas.
A clear idea is vivid and cannot be doubted and distinct ideas cannot be confused with others. Descartes’ aim was to establish what knowledge can be known with absolute certainty. He wanted to use intuition and deduction to discover which knowledge is clear and distinct. The issue with this is that the claim ‘I can only know clear and distinct ideas with certainty’ is not itself clear or distinct.
Descates’ first wave of doubt.
knowledge from senses
Descartes says that his senses have decieved his before (hallucinations, ect.) so they must be untrustworthy. Not all sensory information is unreliable but any individual piece is possible to doubt, but not enough to doubt the external world. It is not, however, possible to doubt all sensory info as we can only know illusions exist because we know that there is also veridical perception.
Descartes’ second wave of doubt.
Sensory perception as a result of dreaming
Descartes says that as he has had realistic dreams in the past, it is possible he could be currently dreaming. We can counter this by saying that reality is much clearer so we can usually tell the difference. Paintings must be based on reality, so must dreams. They are only possible because there is a reality to dream about.
Descartes’ third wave of doubt.
Evil demon hypothesis
Descartes argues that there could be an evil demon tricking him about everything. This questions his sense experience and perceptions, he could be tricked about a priori knowledge too. This calls everything, including logical reasoning, into doubt as it could all just be a deception
Cogito as an example of an a priori intuition
One certain peice of knowledge is” I am, i exist”. Descartes says that existence as a thinking thinking things is ear and distinct. This is knowledge he cant doubt he is thinking (doubting), he must exist to be able to doubt. This is a priori intuition, demonstarating his existence purely from reason and thinking alone.
Response to Cogito
(Hume’s copy principl3)
Hume says all ideas are copies of impressions, and we never have impressions of ourselves isolated from all other experiences. We cannot detect/point to the existence of ourselves, Descartes has not proved this, he made a leap of logic when saying he proved “ I am”. All he has said is that thinking is occuring. Descartes would argue that thoughts require a thinker, why is there a further “I” different from our body, thoughts, experiences, etc?
Response to Cogito
begging the question
In this cogito argument, Descartes is begging the question, meaning he is assuming the conclusion in the premise, which leads to circular reasoning. Descartes’ response is that “ I exist” doesnt require an argument as it is just self evidently true as an a priori intuition.
Arguments for the existence of god as a priori deductions
(Trademark argument)
Trademark argument: Any effect cant be greater than the cause, so Descartes’ idea of a perfect, infinite god can only be caused by a perfect, infinite god. He is neither perfect nor infinite himself. Hume’s response to this would be to say we domt have a clear and distinct idea of perfection and infinity, we just see good/big things and make them better/bigger. This produces ideas that are greater than the cause of the idea
Response for the existence of god
(Hume’s fork)
Hume would say ‘god exists’ fits neither prongs of his fork, so isnt soemthing we claim to know is true/false. All simple ideas are copies if impressions, and since we dont have impressions of god, god cant be a simple idea, so must be complex or made up of others. We get the idea of causation by repeatedly watching things happen, so we have no good reason to believe god is the cause of the idea of god.
Proof of the external world as an a priori deduction
(Wax)
We need reasoning reasoning tk understand that something is still the same object even eith different properties (wax). So we must have a priori knowledge that physical objects can change prooerties and remain the same, senses alone arent enough.
This argument heavily relies on the existence of god, and therefore the validity of the trademark argument.
Response to the proof of the external world
The proof of gods existence relies on having a perfect idea of god. Proof of external world relies on his perceptions being reliable , and theyre reliable because god wouldnt deceive him - this is corcular reasoning. You cant deductivly prove soemthing, only infer causation after many different experiences.
