Sc

Question 1

Normal incredulity

Answer 1

We all naturally have these doubts, day to day, in specific contexts/moments.

Question 2

Philosophical scepticism/doubt

Answer 2

Philosophers generate these doubts deliberately, not in a specific context/moment, but instead because they are philosophically important for thinking clearly about what we can know.

Question 3

Local philosophical scepticism

Answer 3

Philosophical scepticism about some specific area/branch of supposed knowledge

Question 4

Global scepticism

Answer 4

Global scepticism extends doubt without or at least almost without limit

Question 5

Descartes philosophical scepticism/ method of doubt

Answer 5

We should try to doubt all of our beliefs

We should use the most extreme arguments we can think of to do this

Beliefs that can be doubted are not justified and so cannot be counted as knowledge

This doubt is being used for a positive purpose - it is being used as a method for discovering what we know

Question 6

Descartes’ illusion argument

Answer 6

P1: If my senses can deceive me then they cannot and should not always be trusted as a source of knowledge.

P2: My senses do and can deceive me (at least about objects that are small or far away).

C: Therefore, my senses cannot be completely trusted as a source of knowledge.

Question 7

Descartes’ dreaming argument

Answer 7

P1: In order to have perceptual knowledge of mind-independent reality, I need to know that I am not dreaming now.

P2: But I cannot know that I am not dreaming now because all possible accurate perceptual experiences could occur in a dream and therefore dreams are subjectively indistinguishable from accurate perceptual experiences.

C: Therefore I cannot have perceptual knowledge of mind-independent reality.

Question 8

Descartes’ evil deceiver argument

Answer 8

P1: It is possible that a powerful and deceptive being is continuously deceiving me in all my perceptions of the external world and reasoning so that everything I take as true is in fact false.

P2: In order to know anything I need to rule out this possibility.

P3: I cannot rule out this possibility. This is because, regardless of whether it is true or false, my experience/beliefs and my justification for them would stay the same.

C: Therefore, I cannot know anything