Module 2

Learning Goals:

  1. Explain the modern debate between Skepticism, Rationalism, Empiricism, and Phenomenalism using the a priori/a posteriori distinction and the idea that knowledge requires absolute certainty.

  2. Explain the philosophical movement known as Logical Positivism, especially the notions of verificationism and the analytic/synthetic distinction.

  3. Explain Popper's understanding of science and how it differs from the Logical Positivists, while attending to the difference between his theory of science, called Falsificationism, and his theory of scientific progress, called Conjectures and Refutations. 

Lecture 3

Instructions: Please answer 8 of the following 10 questions while, or after, you watch the lecture (or read through the notes).

1. What is the difference between extreme (global) skepticism and (local) skepticism about the external world?

Local skepticism says that I can know my personal experience, but cannot know anything else, while extreme skepticism says I cannot know anything about this world.

So Descartes was a local skepticist?

2. Describe the difference between a priori and a posteriori.

A posteriori is a claim that can be justified using our senses, while a priori cannot be justified using our senses and cannot be justified using our senses, but instead using, like, math.

3. Distinguish between basic rationalism, empiricism, phenomenalism, and idealism. Which do you take to be the most plausible epistemological position?

empiricism makes claims about the external world based on observation, phenomenalism only makes claims about sensation and ignores the outside world entirely, rationalism can only make claims a priori, and idealism says there is no external world- only our ideas and sensations of the external world.

4. Explain the phenomenalist’s objection to basic empiricism. What is the best way for the empiricist to react to this objection? Explain.

5. What was the Vienna Circle? What did they hope to achieve? What movement did they spawn in an attempt to achieve it?

The Vienna Circle hoped to solve all philosophical problems and in the attempt, created logical positivism

6. Explain (a) the analytic/synthetic distinction, (b) the verificationist theory of meaning, and (c) the distinction between observational and theoretical language. How did each of (a)-(c) help the logical positivists to advance their aims?

The analytic/synthetic distinction says that mathematics and such are not of the world, they are how we express things of the world through symbols, which means mathematics is a synthetic experience.

7. What is the best way for us to understand the difference between “observational” and “theoretical” language?

Observational language might say “The round, blue table is to my left” while theoretical language might say “To the left of my field of vision is an object I perceive to be round and blue.”

8. Explain the role of logic in the movement known as logical positivism.

Inductive logic

9. Provide one way of interpreting Quine’s objection to the analytic/synthetic distinction. Is his objection convincing?

  1. If a statement is analytic, then it is immune to revision

    1. once a good proof is given, the theorem is set in stone

  2. No statement is immune to revision

    1. you simply have to get people to use words in a different way

  3. thus, no statement is analytic

  4. therefore, there is no A/S distinction

No, a statement can be analytic and be revised later as knowledge advances. I disagree with Carnap in that premise 2 is false, I think premise 1 is false.

10. What two objections were raised to the verificationist theory of meaning? Are these objections convincing?

Verification is true: is a statement that cannot be verified, therefore verification cannot be true.

Logical Positivism

Early Empiricism

  • skepticism: the idea that we cannot know anything about the world with certainty.

  • external world skepticism: the idea that we cannot know anything about the external world with certainty

    • We can understand our own existence with certainty, but nothing else

  • contra external world skepticism

    • empiricism: knowledge about the external world is strictly a posteriori

      • a claim can be justified based on a sense experience.

    • Rationalism: knowledge of the external world is strictly a priori

      • We may support a claim that is true without requiring a sense experience. i.e. math

The problem for empiricism:

  1. Our senses may not match the structure of the external world.

  2. Without a guaranteed “matching up” to the world, we cannot know if our senses are accurate

  3. If empiricism is true, the knowledge is the external world can only be known through sensation

  4. Therefore: if all we ever have access to are our own sensations, then how can we truly know anything?

  5. All we ever really have access to are our own sensations

  6. Thus, if empiricism is true, then we cannot know anything about the external world

  7. We CAN know stuff about the external world (I’m typing on a computer)

  8. Thus empiricism is false

Phenomenalism: we can only really know about how things appear to us.

The Vienna Circle

A group of philosophers working in Vienna after WWI.

Central Ideas advanced by these two groups:

  • the analytic/synthetic distinction; verification

  • the view of science and logic

Their goal was to settle all problems in philosophy.

If the problem could not be solved empirically, they decided it was either unimportant or not a genuine problem.

They wanted to put an end to metaphysics.

  • observational language- empirical

  • theoretical language- everything else is theoretical

These guys thought the way you

Logical positivists also had a theory of linguistic meaning-

  • verificationism: the meaning of a sentence consists in its method of verification

  • X has meaning if and only if there is a possible method to test the truth or falsity of X

Lecture 4

Study Questions for Lecture 4:

Instructions: Please answer all 5 of the following questions while, or after, you watch the lecture (or read through the notes).

1. What is the “Demarcation question,” and what is Karl Popper’s answer to it?

The Demarcation Problem is trying to distinguish pseudoscience from science.

His answer to it was “falsificationism”

  • A hypothesis is genuinely scientific if and only if it has the potential to be refuted by some possible observation

  • Science must take the risk of being refuted

2. Compare and contrast Karl Popper’s philosophy of science to the Logical Positivists’ along the following dimensions:

a. The standards for knowledge:

b. What science is:

c. How scientific progress is made:

3. Reflecting on the answers you gave to Q2, do you think Karl Popper is an empiricist? Explain.

4. What are the two most serious problems Popper faces? Explain them.

5. How might a defender of Popper reply to the problems you raise in Q4? Is such a defense convincing? Explain.

Goal: Brief description of Popper’s philosophy of science.

Who is he?

He was a critic of the Vienna Circle.

He was a positivist, but not a logical positivist

  • he agreed that we can never be certain about scientific “facts” (fallibilism)

  • He did not think it was because science was committed to induction; science is a “negative deductive enterprise”

  • He thought that we have no reason to increase our confidence in a scientific theory when it passes experimental tests.

What is the demarcation problem?

The impossibility of Confirmation

The idea of falsification is this Impossibility of Confirmation: confirmation is impossible

He thought you cannot prove a theory true through tests, you can only prove it isn’t false.

Conjectures and Refutations

Conjectures are bold, new scientific claims with some sort of predictive element to them.

Refutation is the next step: try to falsify it. If it stands up to scrutiny- good, it stands until it is refuted.

Then broaden the hypothesis to make more predictions or refine the hyp. to create more subtle predictions

Problems for Popper’s views

  1. The eternity problem: we never can stop trying to falsify something- even if it is the truth, so science becomes a waste of time, because we can never find answers

  2. the particularization problem: hyp. must be stated in universal generalization form: “all P’s are Q’s”

    1. one counterexample can refute a generalization

    2. one example can confirm a particularization: “Some P’s are Q’s.”

  3. The no-knowledge problem: if we know nothing, how can you confirm your counterexample is a true counterexample?

  4. The Choice Problem: When choosing between two options, where one has been tested and not proven false and one has not been tested, it is logical to choose the one that has been tested over the one that hasn’t. Popper says we have no reason to choose the one that has been tested.