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Summary notes for Limits of knowledge; scepticism

Philosophical scepticism questions the possibility of knowledge. It doubts the possibility of having any knowledge at all. It challenges our foundational beliefs, such as that we exist or that other people exist or that an external world exists.
Normal incredulity just challenges general common-sense beliefs that aren’t foundational. E.g. someone might have normal incredulity about whether the weather report is accurate.
Normal incredulity always involves ‘local’ scepticism, targeting a

Epistemologists tend not to be sceptics. They use scepticism as an imaginary debate partner to test the strength of their arguments and beliefs.
The function of scepticism is therefore to figure out which epistemological theories could survive sceptical critique, because that’s the only way for them to be valid.
E.g. Descartes’ waves of doubt and how he used them to find a foundation for knowledge – the cogito.

Local scepticism would be within a particular domain or field – e.g. scepticism about the shape of the earth. A person could doubt the shape of the earth, but still thinks the external world exists.
Global scepticism challenges the possibility of all knowledge by attacking all the foundational beliefs through philosophical scepticism.
Foundational beliefs are those minority of beliefs on which the majority of beliefs depend.
They are foundational because if they were false, all the dependent beliefs would consequently be false.
E.g., that we exist, that there is an external world and that other people exist.
All our ordinary beliefs, which are more local, depend on a few pillars like these.
We have all sorts of local beliefs about the world, but they all depend on the belief that there is a world. Global scepticism is targeting those foundational beliefs.
So local involves doubting members of a category, whereas global is doubting the entire category.
Normal incredulity is always local.

Descartes used scepticism in his methodological doubt – applying scepticism to his beliefs to try and find something that he cannot doubt – that defeats scepticism.
The first wave doubts individual experiences because he has seen illusions before, so any experience could be an illusion.
However – he notes that the entirety of his experience couldn’t be an illusion.
The second wave doubts all his experience though, since he could be dreaming.
However – he notes that logic and mathematical knowledge would still be true even in a dream.
The third wave doubts logic and maths. An evil demon could be confusing him about them – when he thinks ‘1+1=’ the demon could then be making him think ‘2’ when really it’s 3.
However – even if he is deceived by an evil demon, he would still have to exist to be deceived. So his existence cannot be doubted – since to doubt your existence requires that you exist. Descartes then attempts to build on this knowledge as the foundation to other knowledge in order to defeat scepticism.

Scepticism claims knowledge is impossible
Reliabilism claims knowledge is reliably formed true belief
If we were in a sceptical scenario (dreaming, demon etc) – then we couldn’t gain any true beliefs.
However, it’s possible that we aren’t in a sceptical scenario. So, it’s possible that some of our beliefs are true and reliably formed.
So, it’s possible that we have knowledge.
So, scepticism is false.
Scepticism argues we can’t justify whether we are in a sceptical scenario or not.
Reliabilism avoids this argument by removing justification as a criteria for knowledge. It is what’s called ‘externalist’, meaning dependent on objective facts about the world, rather than subjective reasons for beliefs within our mind.
If it is a fact that a person has gained a true belief from a reliable process, then they have knowledge. They might themselves not be in a position to actually know whether they are in a sceptical scenario or not. But if they aren’t, they can have knowledge.

Limits of knowledge; scepticism model essay plan

Note that this model essay plan is merely one possible way to write an essay on this topic.

Points highlighted in light blue are integration points
Points highlighted in green are weighting points

I haven’t finished this essay plan, but it’s essentially compiled from things already explained in other essay plans:

Intro:

Explain scepticism – the view that knowledge is impossible & sceptical arguments inc. Descartes’ waves of doubt.

Paragraph 1:

Descartes’ response: intuition & deduction thesis

Just the cogito part – since if that fails then his laters parts fail.

Accept the cogito, but deny his argument for God (without which his argument for the external world fails) using Hume’s fork.

This leads into the empirical theories and whether they can solve scepticism better.

Paragraph 2:

Locke & Russell’s empiricist attempt

Paragraph 3:

Either idealism or reliabilism

Idealism

Berkeley argues that reality is mind-dependent, ideas within minds.
We have immediate introspective access to the ideas in our mind, and therefore to reality.
This undercuts the standard sceptical arguments which attack our ability to know whether there is an external world. Berkeley is claiming reality is not external but internal.
His master argument aims to prove this…

Counter

Solipsism critique: Berkeley might counter scepticism about the external world, but seems to just open us up to another form of scepticism – about the existence of other minds.

Evaluate

Berkeley attempts to solve this through his proof of God.
He think his master argument proves idealism, that to be is to be perceived.
The only way to explain perceptual orderliness, regularity and things changing when we aren’t perceiving them, is if there is a mind perceiving all things at all times which is the ultimate origin of our perceptions.
Berkeley claims that would be a God.
This would prove there is at least one other mind – God. So this would solve solipsism.
However it all depends on Berkeley’s master argument proving idealism which then proves God.
But it fails, because it assumes the idea of a thing is the same as the thing itself.
Certainly as soon as we think of an unperceived tree, the idea of it arises in our mind and is mind-dependent. But it’s just an assumption to say the tree has no mind-independent existence aside from our idea of it.
Berkeley is assuming the tree is just the idea itself. He’s not proving that.
So, Berkeley has no way to prove idealism, or therefore God, or therefore defend against scepticism of other minds.