The intuition and deduction thesis

What is a priori knowledge? What is the definition of reason and what does it enable us to do? What are the two ways in which we can justify a priori knowledge? What’s an example?

A priori knowledge is knowledge which is justified by reason. Reason is the intellectual, rational, logical faculty of our mind, by which we can make logical inferences and with which we can recognise no prove a priori truths, and demonstrate a priori falsehoods. We can justify a priori knowledge through intuition and/or deduction. Example: ‘all bachelors are unmarried.

What’s the definition of an a priori truth/falsehood?

A truth/falsehood that can be known through reason alone, not by experience.

What is a priori knowledge? What is the definition of reason and what does it enable us to do? What are the two ways in which we can justify a priori knowledge? What’s an example?

A priori knowledge is knowledge which is justified by reason. Reason is the intellectual, rational, logical faculty of our mind, by which we can make logical inferences and with which we can recognise no prove a priori truths, and demonstrate a priori falsehoods. We can justify a priori knowledge through intuition and/or deduction. Example: ‘all bachelors are unmarried.

What’s the definition of an a priori truth/falsehood?

A truth/falsehood that can be known through reason alone, not by experience.

What’s a posteriori knowledge? How can we gain a prosteriori knowledge?

A posteriori knowledge is knowledge justified by experience. Experiences are impressions in our mind, these can be sense impressions (e.g visual experiences), hallucinations or internal impressions (e.g emotions). Can be gained by using our 5 sense, doing a scientific experiments and/or reading/ surveys. E.g I am currently sitting down.

What’s the difference between analytical and synthetic truths?

Analytical truths are true by definition (are tautologies) e.g ‘twins are two in numbers, whereas synthetic truths are not true by definition but instead are true because of the facts of the world e.g the Eiffel Tower is in Paris.

What’s the definition of deduction?

Deduction is the ability to infer what must follow from other facts.

What’s the definition of intuition?

Intuition is a single act of the intellectual whereby it inwardly ‘looks upon’ a proposition and you just understand immediately that it’s true e.g 1=1.

What example does Descartes give for an idea which is clear but not distinct?

Leg pain- it is hard to distinguish the pain from the true cause.

What do rationalists/ does Descartes believe about intuition and deduction?

Rationalists believe that we can gain knowledge of the facts of the world (synthetic truths) through intuition and deduction.

What four rules did Descartes devise for gaining knowledge?

1) Accept only beliefs that can be recognised clearly and distinctly to be true. 2) Break down every problem into its smallest parts. 3) Build up the arguments systematically in order. 4) Carefully check to ensure no steps are left out.

What are 3 examples of Descartes ‘clear and distinct ideas’ (propositions which you can know by intuition alone)?

the cognito, ‘the cause must be as least as great as the effect’ and ‘deception is an imperfection’.

What does ‘clear’ and ‘distinct’ mean to Descartes?

An idea is ‘clear’ if it is bright and present to the mind and an idea is ‘distinct’ if it is sharply separated from other ideas and it’s purity. An example of a clear and distinct ideas is that ‘2 + 3 =5 .

What’s the criticism to Descartes ‘clear’ and ‘distinct’ ideas that they are not clear and distinct enough?

Leibniz argued that we need a more clear and distinct account of ‘clear’ and ‘distinct’ ideas to able to apply these usefully as a criterion of truth, relying on a feeling is not enough.

What’s the explanation of the criticism to Descartes ‘clear’ and ‘distinct’ ideas of them being a quick generalisation?

Descartes put the success of the Cognito down to the fact that its truth can be grasped clearly and distinctly, he then generalises this principles and claims that any belief that he can conceive clearly must be true. It is a generalisation and doesn’t mean that all beliefs can be made to knowledge by this.

What’s the criticism of Descartes clear and distinct ideas of it being only an internal criterion for truth?

You cannot tell that a belief is true just by focusing on the belief and using no external criterion, it goes against the correspondence theory of truth. the Cognito may be an exception to this criticism as it may be termed self verifying.

How does Descartes gain knowledge about the world?

He reaches the clear and distinct idea that he exists via intuition, from this he is able to use deduction to know other truths (sometimes also using intuition).

What is/ how does the cognito work? Does Descartes believe that the cognito is an intuition or a deduction?

If you are doubting your own existence, you are doubting and if you are doubting you must exist, ‘I think therefore I am’. Descartes believes the cognito to be an intuition as it is so clear and distinct (to the mind, the fact is self evident).

What’s the cognito in and argument?

P1) I am thinking P2) (hidden) I cannot think without existing C) Therefore, I exist

What does it mean when it is said that the Cognito is a self-verifying thought?

The truth of the Cognito is revealed in the very act of performing it.

What does it mean when it is said that the Cognito is a transcendental argument?

It claims that a specific feature of the world (existence) is a pre-condition for doubt to exist). This is also true for thinking.

What is Bertrand Russell’s empiricist response to the Cognito/ the issue of different thinkers?

You can only be sure that you exist why doubting your existence, you may cease to exist while you are not e.g it’s a different person doubting each time, each of which has been has been given the memories of the previous person. There is no enduring ‘I’/ thinker that exists

What are issues with Bertrand Russels/ the issue of different thinkers criticism to the cognito?

They are being too overly sceptical, not all doubt is rational (which Descartes argues), we have to assume some things (e.g we are sane), some beliefs are too far-fetched.

What is David Humes empiricist response to the Cognito?

Hume argues that all of knowledge must originate in impressions, therefore if we have a concept of ourself, it must originate from impressions, however when we look into ourselves, we are aware of our perceptions of the outside world but not of ourself. The concept of ‘self’ refers to a bundle of perceptions .

What are criticisms to David Humes criticism to the cogito?

Hume assumes the existence of a permanent substantial ‘I’ in his argument as this is what is doing the looking.

What’s a criticism of the Cognito of radical doubts and that there may be no thinker at all.

Perhaps thoughts don’t need a thinker, the transcendental argument may be incorrect.

What is Descartes trademark argument in full?

P1) The cause of anything must be at least as perfect as its effect. P2) My ideas must be caused by something. P3) I am an imperfect being. P4) I have the ideas of God, which is that of a perfect being P5) I cannot be the cause of my idea of God P6) Only a perfect being (God) can be the cause of my idea of God C) God must exist.

What is the summary of Descartes trademark argument?

The cause of anything must be at least as great as its effect, we (imperfect beings) have the idea of God who is a perfect being, god must have caused the idea of himself/ God and so he must exist.

How did Descartes make his trademark argument?

He used intuition (the cause must be at least as perfect as its effect) and then used deduction to reach the conclusion that God exists.

What’s the explanation of the criticism of the causal principle to Descartes trademark argument?

What’s a counter argument to this?

The casual principle states that ‘the cause of something must contain at least as much reality as does the effect’. The casual principle may be true in regards to the physical world however may not be true with regards to ideas, the physical cause of the idea may not be as great as the idea e.g Hume augmentation (augmenting qualities).

While you can augment ideas, you cannot create the ideas of an infinite or perfect being.

What’s a criticism to the casual argument regarding the physical world?

What’s a response to this?

It seems possible to produce something with more perfection or reality than its original cause e.g lighting a match causes a bonfire.

there must have been lots of chemical energy.

What’s a criticism to the trademark argument as to whether we can really have the idea of perfect/ infinity?

We do not have a clear idea of a perfect god or infinity, we understand it infinity to be to opposite of finite as we cannot truly understand it. this means that there is no issue of to where the idea came from, us as imperfect beings could have produced it.

How to Humes Fork/ empiricists response to Descartes?

We can only have knowledge of two types: matters of facts or relations of ideas.

What is Descartes proof of the external world?

Step 1: P1) The will is a part of my essence P2) Sensation is not subject to my will C) Sensations come from outside me

Step 2: P1) There are two possible sources of the origin of sensation: God or matter P2) I have a strong natural inclination to believe the come from matter, and I have no faculty by which to correct his belief P3) So if the origin where in god, God would be a deceiver C) Sensations originate in physical objects.

What’s a criticism of step 1a?

Sensations may come form a part of use which we are not conscious of e.g dreams are not subject our will yet they come from inside of us.

How does Humes fork respond to Descartes

All relations of ideas are an analytical truths (true by definition) whereas all matters of facts require experience of the world, therefore reason alone cannot tell us anything new or substantial about the world, only experience can.

Relations of ideas are analytical truths(true by definition and are true regardless of the state of the world) . Matters of facts require experience of the world. Reason alone cannot tell us anything new or substantial about the world, we need experience for this. Reason alone can only tell us only tell us things which are true by definition, all other knowledge hand to be gained form experiencing the world. Reason can only lead us to analytical truths, they cannot prove facts of the world. Descartes is proposing a third category for knowledge- synthetic a prior knowledge.