PHIL 101 Lecture 8: The Problem of Induction

Empiricism

Belief that sensory experience provides a foundation for knowledge.

Skepticism

Use of illusions, dreams, and hallucinations to challenge the reliability of sense experience.

Reliable Impressions

Impressions that come from using multiple senses together.

Expectations about the world

Based on past experiences, but the reliability of reasoning from past to future is questionable.

David Hume

Empiricist who provides skeptical arguments against empiricism. Believes knowledge is limited and unjustified beliefs are formed.

Hume’s Argument

Distinguishes between analytic (relations of ideas) and synthetic knowledge (matters of fact).

Synthetic Knowledge

Involves expectations about the future, lacks a basis for future conclusions, and questions logical arguments for expectations.

Deductive Arguments

Aim for valid inferences.

Inductive Arguments

Reason from observed premises to unobserved conclusions.

Inductive Arguments Validity

Strictly invalid.

The Problem of Induction

Questions the justification of beliefs about the future due to invalid inductive reasoning.

Hume's Argument (Problem of Induction)

We must reason inductively, inductive reasoning is invalid, to reason invalidly is irrational, therefore, we must be irrational.

Solution 1: No True Scotsman Ploy

Response to a counterexample by claiming it's not a true member of the category.

The No True Scotsman Ploy

Hypothesis: \"All Scots are mean.\", Counterexample: \"Andrew Carnegie is generous!\", Response: \"Carnegie is not a true Scot.\"

Sceptical Response (No True Scotsman)

Argument shifts from synthetic to analytic by dismissing all counterexamples.

Solution 2: Appeal to Inductive Principles

Adding an inductive principle (PUN) to validate inductive arguments.

Sceptical Response (Appeal to Inductive Principles)

Questions the justification of PUN, leading to infinite regress, and notes that PUN is too strong.

Solution 3: Probabilism

Forming probabilistic judgments using past experiences.

Sceptical Response (Probabilism)

Argument remains invalid, requiring a probabilistic PUN and not solely based on past instances.

Solution 4: Deductivism/Falsificationism

Denies inductive reasoning; general conclusions are tested deductively.

Sceptical Replies (Deductivism/Falsificationism)

Questions if conclusions are jumped to inductively and challenges the belief without proof.

Bertrand Russell on Induction

Without an answer to Hume, there's no intellectual difference between sanity and insanity.

Conclusion

The problem of induction is a serious challenge for empiricism, leading to embracing irrationality or finding the conclusion intolerable.