Thread: "Английский язык -- самый трудный в мире".

I think that the sentence "Но, я все же думаю, что мы можем измерять трудность языков на научной основе" is completely acceptable. It means that measurement is possible in principle and it is a fact. Actually I'm not so good in explanations so a couple of examples should help:

Жара может изнурять - a statement, a fact
Жара может изнурить - it can do it in some specific circumstance

Жириновский может изменять гравитацию Земли - a statement, a fact
Жириновский может изменить гравитацию Земли - if he wants he can do it

Мы можем измерять - a statement, a fact
Мы можем измерить - if we wants we can make some measurements

Originally Posted by delog

I think that the sentence "Но, я все же думаю, что мы можем измерять трудность языков на научной основе" is completely acceptable.

I did not say it was impossible. I said "измерить" suits better for that particular example. And "измерять" is possible, but it involves some subtle nuances. If speaking in general, "измерить" just sounds more natural in the context provided by Valda.

And as to your examples, Delog: yes, they do work. But there are even more nuances, and your examples do not show all of them.

Consider this one:
Древние Греки догадались, как можно измерить Землю.
but not "измерять"!

I hope you feel the difference. Unfortunately, there is not a simple single rule for the aspect choice.