[ Source: ] At this point I’ve established that the perfect and the perfective are two separate concepts. However, there’s a conceptual relationship between these two even if there’s not an intrinsic formal one. It’s intuitive that if you’re trying to convey that something in the past is relevant in the present, you’re likely going to refer to that past situation as an undifferentiated whole rather than describing its internal structure. The point you’re making when you’re using the perfect is probably really about the present rather than the past – you’re
invoking the past to describe the present, and [1.] the perfective lends itself to that kind of description.
[2.] “Perfect” and “perfective” share a stem for historical reasons; the reflex of English “perfect” once meant “complete”. Both terms are essentially metaphors that unfortunately use the same imagery for different concepts.
I understand, and so ask not about, 2; the French and Latin etymons did mean 'complete'.
I do not understand 1. How does the perfective 'lend itself to'
invoking the past to describe the present?
Besides 1 and 2, what else do these two Aspects share?