The Problem of Induction and Hume

Intro to Philosophy A Revision

Hume’s fork

A critical epistemological tool that divides all objects of human reason or inquiry into two distinct categories:

1. Relations of ideas

2. Matters of Fact

Relations of Ideas (Hume)

a proposition which is certain to be true; discoverable by the mere operation of thought.

Matters of fact (Hume)

propositions that are not certain to be true; discoverable in some way other than mere operation of thought.

Inference

when an individual assumes that other propositions are true and reasons that P follows from them. 

Deductive inference

when the truth of the other proposition logically guarantees that P is true eg. I was born on the moon, therefore someone was born on the moon.

Non-deductive inference

The truth of the other proposition makes it more 'probable' that P is true.

Enumerative inductive inferences

Assume a number of particular instances and reason that P follows as a generalisation (eg. everyday in the past, the sun has risen, therefore the sun will rise tomorrow)

Abductive inferences

assume one or more propositions and reason that P follows as the best explanation (eg. theres a correlation between sun exposure and sunburn therefore sun exposure causes sunburn)

Induction (broad sense)

non-deductive inference, inference where the premises dont logically entail the conclusion

Induction (narrow sense)

generalisation from experience

The problem of induction and the “black swan”

Eurasian observers did not know of black swans and thus concluded that swans were all white.

Uniformity of nature

the thesis that the laws of nature that have been true thus far will continue to be true tomorrow

Hume’s problem of induction

How can a generalisation inductively inferred from particular instances be justified?

Grue

an object is grue at time t just in case the object is (i) green at t, and first observes in 2025 or earlier; (ii) blue at t and first observed after 2025

Goodman’s new problem of induction

How can we identify the predicates that we can legitimately use in inductive inference?

Bleen

an object is bleen at time t just in case the object is (i) blue at t, and first observes in 2025 or earlier; (ii) green at t and first observed after 2025

Demonstrative reasoning (Hume)

“that concerning relations of ideas”

Moral reasoning (Hume)

“that concerning matter of fact and existence”

Fiction (Hume)

we can make up anything from our simple impressions eg. unicorns

Belief (Hume)

a combination of imagination and a certain sentiment that we cannot control that suggests to us that our imaginings correspond with reality.