What is the idea of induction in science teaching?

Answer 1

Induction is the basis of the scientific method, its alternative is deduction. If you deduce something, it should in theory be absolutely correct within the context of its assumed premises, ie the premises dictate the answer. If you induce something it gets stronger the more culmulative the evidence, but is never a 'proof'. That's why the theory of evolution for example, is a 'theory', because its based on observation rather than deduction.

Example of deduction:

P1: All bachelors are unmarried
P2: Alastair is a bachelor
C: Therefore, Alastair is unmarried.

That's absolutely correct. The premises (P) could in fact be wrong, but with the premises assumed the conclusion (C) that I'm unmarried is certain.

Example of induction:

P1: Alastair lives in the UK
P2: Alastair is unmarried
P3: Doug lives in the UK
C: Therefore, Doug is unmarried

The limitations of induction become pretty obvious. C becomes stronger the more powerful and numerous the premises are. That's why scientists tend to talk about 'supporting evidence' and mathematicians tend to talk about 'proofs'.

Answer 2

There is such a thing (in maths anyway) as proof by induction... it basically goes

To prove a statement A:
Assume A is NOT true
Then show that this implies that some other statement B must be true
Show that (in reality) B is false
Then - by induction - A MUST be true QED

Obviously the crunch point in practice is having some idea as to what statement B should be!!

Answer 3

That's an excellent example, guesswest. And, as it turns out, I'm not married *and* I don't live in the UK ☺


Doug