What words are aquer?

Question

Art, the arbiter, poses this riddle to George, the guesser:

Some words are "aquer", some are not;

The difference is simple yet profound.

If you want to find an aquer word, you had better be certain,

And not beat around the bush.

Politicians will be good at this;

Scientists, not so much.

After this, Harry the hint-giver, who knows the secret, enters into a conversation to try to help George figure out the riddle.

Harry: For example, abacus is aquer.

Art: Correct.

Harry: And so is beatific.

Art: Correct.

George: OK, let me guess one: Is werewolf aquer?

Art: No.

George: How about apple?

Art: No.

Harry: But banana is.

Art: Correct.

George: OK, I think I might see the pattern. So, horticulture would be aquer.

Art: Correct.

George: But agriculture would not be.

Art: Actually, no, agriculture is also aquer.

George: Hmm, that destroys my idea... (Thinks for a bit.)

George: Is aquer itself an aquer word?

Art: No.

Harry: For another example, olfactory isn't aquer, is it, Art?

Art: No, it's not.

Harry: But nasal is.

Art: Correct.

At the end of this conversation, George is left utterly perplexed as to what the criterion might be. Can you spot it?

Answer 1

The trick to this is that

the words themselves don't actually matter: the "aquer" words are those that are in declarations. If you ask, they are not aquer; if you make a statement, they are.

The opening riddle gives hints to this:

"You had better be certain" hints that making statements is necessary. "Politicians will be good at this; Scientists, not so much" plays with the stereotype that politicians make statements that they aren't sure to be true, and references the fact that science is all about inquiry.