Los ninos creian

Question

I just took a quiz in Spanish over imperfect/preterite and my teacher, a native speaker, marked this wrong.

Los ninos creian el cuento. And indicated that it should be creyeron el cuento instead.

I thought that since this was a mental state, it would be imperfect. Any explanations'

Answer 1

The sentence was actually just on its own without any context, so I assume that creyeron is really what she meant. Thanks for the very concise explanation.

Answer 2

Not enough information is given. Both can be correct, but it is more difficult to find a situation where "creían" would be the right option.

Imperfect (e.g. creían) is used when you are looking at a past story from inside, rather than from outside once it is finished. So, if you say "creían" and "el cuento", you want to imagine it while they kids werer believing the story... and keep that thought alive. Obviously, if you are telling the story from within, you don't want the tale to finish yet (in the past), probably because you are about to say something else while they were still believing and the tale was being told. Imperfect leaves the "believing" nearly in a suspended animation, until another sentence tells us otherwise. We don't know whether the story is still being told, and we don't even want to think whether this will ever end... for the moment. Is this what you meant to say?

On the other hand, preterite is used to talk about finished things from an outside perspective. The kids believed the tale, end, the tale finished, end, and now we are ready to move on to the next event. This is more likely to be what you wanted, isn't it?

This is the real difference between imperfect and preterite: with imperfect we are not interested in the event as a finished one, because we want to picture it as it happens, so the end is not mentioned, and we normally cannot assume that we even reached an end. Preterite implies finished events that we contemplate in their totality (even if the verb is "to begin").

Those rules about mental states are pseudo-rules that only lead to "exceptions" and frustration.