(1) Every bachelor is unmarried.
I know this is one of the most famous examples (intensionally) denoting analytic and a priori propositions. No problems yet.
(2) Every apple is a fruit.
This one is a bit more confusing. At first glance, I thought it was analytic, but after a while I’ve come to notice that I can’t be very convinced because of the following sentence:
(3) Every apple is molecular.
This appears to be obviously a posteriori; no one would know if this is true like in the 8th century. I knew Kripke made a distinction among necessity, analyticity, and a priority. So I was like “this may be something like an a posteriori analytic proposition or whatnot.” (Is it?)
But the real question I haven’t given an answer to myself yet is that if the last sentence is a posteriori, what about the first one? Can it still be considered a priori? It seems it is still widely assumed so, but I can’t see the differences among those three sentences. I would really appreciate it if you would answer me.