What is an inductive argument, and what does it mean for one to be "strong"?

An inductive argument aims to show its conclusion is probable given the premises; it is strong when true premises make the conclusion likely true (but not guaranteed).

Inductive arguments try to show that their conclusion is plausible or probable given the premises — not certain.

• Strong inductive argument: if the premises are true, the conclusion is probably true; the premises give probable but not logically conclusive grounds.
• Weak inductive argument: the conclusion probably does not follow from the premises.

The classic example and its trap:

(P1) All swans observed so far have been white. (K) Therefore all swans are white.

This felt strong — until black swans were observed in Australia. That's Karl Popper's falsification point: a single counter-example overturns an inductive generalisation. Inductive arguments can always be revised by new evidence.

Tip: Induction generalises beyond the observed cases, which is its power and its risk: no number of white swans proves the next one is white. That's why scientific claims stay open to revision.