However, is this how the Greeks viewed their verbs? Well, at least according to one of their grammarians, Dionysios Thrax, not really. He says (my translation), "There are three times: present, past (having gone by), and future (about to be). The past has four different sections: imperfect, perfect, pluperfect, and aorist. There are three relationships between these: present to imperfect, perfect to pluperfect, aorist to future" (the original). He views the verbs more in terms of time (though, that last line is interesting...I might return to that sometime).
The next question is whether or not the Greeks' own view is important. If someone calls all trees trees without recognizing the distinction between the different types of trees, he isn't completely wrong but he lacks the botanical sophistication to point the distinctions out. Or maybe a better example might be the difference between an interior decorator and a normal guy. To the normal guy there is just green, maybe a dark and a light green, but green nonetheless. To the interior decorator, though, there is forest green, jade green, emerald green, sea green (I am a normal guy; those were the only crayons I could think of). The interior decorator has an increased sophistication when dealing with colors.
So maybe, the Ancient Greek grammarians lacked the needed sophistication to recognize what was truly occuring in their language. Maybe they only saw the verbs in context and, therefore, drew conclusions only from the context, which usually showed tense, but they did not have the linguistic sophistication that we have now to look at unaffected meanings.
We have two views (there are other views out there as well). One uses modern linguistic tools to examine what authors have written and considers what might be occurring in the text. The other is looking at the language from within but without the current linguistic tools and discussions.
Which is correct?