Hume's Problem with Induction What is induction? Can be said that induction is any reasoning from premises concerning the observed to the unobserved. Or perhaps that induction is any reasoning from premises concerning the observed to the unobserved by extrapolation. This is an enumerative induction. Enumerative induction - reasoning that draws a conclusion concerning a class/population by extrapolating from premises concerning a sample of cases. Typically the sample will be observed and the cases to which we extrapolate are as yet unobserved. Examples: . All observed As are Bs therefore all As are Bs . All observed As are Bs therefore the next A will be a B . Most observed As are Bs therefore most As are Bs . Most observed As are Bs therefore the next A will be a B The claim of Hume's problem A belief acquired by inductive reasoning is not justified (and does not constitute knowledge) because it cannot be justified by deduction, and any attempt to justify it by non-deductive means will be circular and so will fail. The conclusion of an inductive argument is not deducible from its premises therefore inductive reasoning cannot be justified. P1. The conclusion of an inductive argument is not justified by deduction. P2. Any attempt to justify the conclusion of an inductive argument by non-deductive means will be circular therefore C. The conclusion of an inductive argument is never justified (by that argument). therefore C. The conclusion of an inductive argument is never known (by that argument). Experience justifies induction? If induction cannot be justified by demonstration (logic, maths), then perhaps it can be justified by the fact that it works. Think for a moment about how much we rely in induction in our everyday reasoning Everyday induction is not perfect, but it is highly reliable (or we would not be here) Past experience shows induction to be highly reliable therefore we should expect induction to (be highly likely to) produce a true conclusion on this occasion. Hume's Problem: the only way to justify induction is with induction. Inference to the best explanation. We know things about: laws of motion, atoms and the cause of dinosaur extinction, through enumerative induction.
Evidence for the atomic hypothesis: · Law of constant proportion · Isomerism Explanation for the K-Pg extinction: · Evolution · Volcanic eruption · Meteor Evidence: · Rapid extinction · Global · Iridium anomaly Because the evidence backs the meteor explanation, that is the inference to the best explanation The System of IBE: Scientists will consider all possible explanations and then select the potential explanations actually generated. From these selected explanations, they are then ranked in accordance to evidence and the one selected as most likely by the evidence is considered the best inferred explanation. Problems with IBE . Hume's objection - As IBE can be considered similar to enumerative induction, it suffers the same objection. . Under consideration - We have no idea whether the selected hypothesis include the true hypotheses. In order for the system to