Lecture 9.1 Moore

Modern scepticism is fundamentally similar to Descartes’ scepticism, characterized by its emphasis on the need for strong evidence to substantiate knowledge claims.
Evidence Principle (EP): Central to modern scepticism, stating that I know that p only if my evidence for p completely rules out the possibility that p is false. This reflects Descartes’ insistence on achieving epistemic certainty before claiming knowledge.
Distinction: While Descartes focuses heavily on ‘rational insight,’ modern scepticism extends the conversation to the implications of evidence and its sufficiency.

The Zebra Example explores situations where evidence does not conclusively eliminate alternatives, such as:
- Even if evidence suggests an animal is a zebra, it does not rule out that it might be a painted mule.
The Phone Example considers technological errors:
- A phone might display the correct time, yet this can be false due to an unreliable source, illustrating how evidence can be misleading.

The rationale is grounded in the claim that if evidence permits any possibility of falsity, then knowledge ought to be called into question.
- For instance, truly knowing that an animal is a zebra demands ruling out the chance of it being deceptively painted, thus complicating the acquisition of knowledge.

Internalist Perspective: Argues that knowledge can still be claimed even when evidence is fallible.
- Example: One can know it is likely a zebra despite potential shortcomings in evidence.
Externalist Perspective: Introduces Reliabilism which posits that justified belief can exist without absolutely perfect evidence.
- Knowledge may rely on reliable processes rather than complete scrutiny of every piece of evidence.

The argument structure suggests that the evidence we have does not definitively rule out the scenario of being a brain-in-a-vat (BIV).
- According to sceptical reasoning, unless we can rule out all possibilities of falsity, knowledge—including knowledge of our corporeal existence—is unattainable if the BIV hypothesis remains plausible.

The argument emphasizes epistemic conclusions focusing on what can be known rather than delving into metaphysical claims about reality.
The assumption encompasses the possibility of being a BIV while refraining from committing to its likelihood of truth.

The phenomenon of ignorance in a broader context often leads to sceptical viewpoints.
Issues of differentiating subjective knowledge from objective action complicate the discussion of knowledge reliability.
- It highlights how confidence in beliefs, along with probability estimations, does not dismiss the fundamental questioning of how reliable those confidences truly are.

Three primary responses include:
- Moorean Response: Asserts that knowledge of external objects is possible through everyday experiences, like proving the existence of hands by seeing and feeling them.
- Sensitivity Response: States that for knowledge to be genuinely held, one should be able to recognize that if it were false, one wouldn't believe it.
- Contextualist Response: Claims that the context alters standards for knowing, suggesting that what counts as knowledge can vary based on circumstances.
- Although each response provides valuable insights, limitations exist that can render some of them inadequate against sceptical challenges.

An example presented by G.E. Moore involves holding up two hands, leading him to conclude the existence of external objects through immediate experience:
- ‘Here is a hand’ and ‘Here’s another hand’ thereby asserting an external reality.

Skeptics may deem Moore's proof unconvincing due to its failure to offer a general, universal proof for the existence of external objects.
- Validity challenges arise regarding the premises and underline important philosophical inquiries about the nature of existence and knowledge.

The sceptic posits that Moore's proof is insufficient because Moore cannot verifiably prove he possesses hands, which leads to further philosophical implications.

Moore defends the position that knowledge does not always necessitate proof, using the example of knowledge related to established facts that one can understand without extensive evidence backing them.

Moore's perspective champions a common-sense interpretation of knowledge, framing experiential knowledge as foundational.
It emphasizes the need to assess the dichotomy between scepticism and non-scepticism, leading to profound philosophical explorations regarding what it means to truly know something.

In this discussion, the skeptic argues that lacking knowledge regarding not being a BIV invalidates the claim to have hands.
Conversely, non-skeptical reasoning suggests that knowledge of hands inherently implies knowledge of not being a BIV due to tangible experience.

Both sceptics and Moore recognize the Closure Principle: suggesting that valid inference from known truths can extend knowledge.
- For instance, knowing the location of a continent implies an understanding of its geographical relationships.

Support: Proponents argue that knowledge can logically extend through valid reasoning, observing real-world scenarios utilizing deductive logic.
Opposition: Critics highlight situations where abstract conclusions lead to instances that may not equate to functional knowledge as perceived in reality.

Lottery Example: This illustrates that betting on a lottery can lead to knowledge claims that may misalign with the actual outcomes, thus prompting doubts about certainty in knowledge.
Zoo Example: Knowledge about a zebra, while seemingly straightforward, could be questioned under the potential that evidence might mislead, suggesting a complication in affirming knowledge conclusively.