Functions are not seen, but must be understood. (Catherine Blanche King, private communication)
I am grateful to Catherine for responding with valuable comments providing needed context to the quote. Herewith, her comments:
Glad to hear from you.
About that quote, it’s really brief but probably needs to be in some contexts at least.
But the underlying issue is one of an already-learned idea about opening our eyes and seeing, and then wrongly equating that common activity with what happens when we understand. The more nuanced point, then, is that we do sense, but also that WHAT we sense we also ask about . . . so that the wrong-view that seeing equates to understanding can give way to the right view that wonder, questioning, and then having insights is what gives way to understanding and then even to knowing.
But the fundamental issue is to understand that the sensible, and much more, is also intelligible; and that we understand that intelligibility through intelligent process.
Just knowing that intellectually, however, is only a beginning to changing one’s already-set but erred viewpoint, which is usually set in our childhood . . . so it takes a good amount of thought to unearth that view and to experience change at the luminous core of our understanding.
As always, good luck and good insights as you undergo your work.