This thread is to discuss the question in the title.
It seems to me that this aphorism, which most of us seem to agree is a good one, needs to be followed up with more explanation of what exactly *is* the proper way for us to view the "perfect" in relationship to "the good?"
Let's also presume that we don't immediately jump to the reductionist "there is no perfect" and "there is no good," although that may be a perfectly reasonable option that we can include in the discussion.
Presuming we are talking to non-philosophers and want to give people practical advice, would we start with something like:
"The 'perfect' of a thing is a concept that we use to visualize what the 'best' of that thing would be, and by visualizing that concept of the 'best' of that thing, we can more easily work toward our target of approximating it. And even though we know from the start that the 'perfect' is not attainable for us, it still serves as a very valuable tool for us in calculating out actions, because there is no way we can hope to come close to a goal unless we start out knowing what the goal is."
I think we will see in discussing Cicero's objections to Epicurean philosophy that a lot of it amounts to stressing "the perfect" in a way most of us will consider to be unattainable. What then would we expect the ancient Epicureans to have said about this topic?