Well I think truth is the commonsense concept of a statement’s correspondence with reality. Statement X is true if and only if X is the case in reality. This is an objective relationship.
And I think certainty is a kind of assurance that something is true. It’s a type of positive argument that statement X is true. It’s a kind of positive proof that X is true.
The alternative to being certain that X is true is to just conjecture that X is true. Popper says this works just fine and that we don’t need certain foundations to build on. We can just conjecture things.
CR says that certainty is not attainable and that its pursuit is vain. And it says all our knowledge is conjectural.
What I said before might also help clarify the distinction:
Do you see two different concepts here?
CR says induction is logically impossible, and that therefore neither Newton, Darwin, nor anyone could have arrived at any conclusion using induction.
What do you think of the problems with induction Elliot talks about in the topic article? Do you think they’ve been adequately answered somewhere?