what is the threshold between "knowing" something vs memorizing? Like for example, if I'm watching Jeopardy! and the answer is the president of the united states in the year 1904. Maybe with a little luck Mayim sneaks in the word "bull" or "moose" but I bet for most of us our brains would have to go back to memorizing the presidents in order...I know for myself personally I do not know all the presidents in order off the top of my head, but I do have a few milestones that I know for sure...like Lincoln being the president during the civil war, Wilson being the president during WWI, as an example. Whereas like someone who really KNOWS history knows oh yeah, 1904 that's when they started building the Panama Canal and that was like a whole thing for Teddy Roosevelt so yeah 1904, Teddy Roosevelt was the president. But like, if you ask me who was the president in 2011 I don't need to try to remember any order, I know it was Obama b/c I was an alive adult at the time so like, i didn't really have to memorize that, I feel like I just inherently know in my bones who the president was in 2011.
Or like, another example, my friend Carl like, really KNOWS music. Knows music theory. And I can just be like "hey Carl how do you play a D# with a suspended 7th?" and like, I just made that up because i'm pretty sure all those words i just said are actual things, and there are a few chords i've memorized like Dsus4 that's a pretty common one, but I say that to Carl and Carl is like okay yeah lets see so you need to cover these notes for the D# and then to suspend the 7th that's X fret on the Y string.
I'm sure i could come up w/ several more examples, but like, what would you consider the threshold between knowing vs memorizing? Or is this a distinction without a difference?