This is quoted a lot at the beginning of my favorite LessWrong article, “Truly Part if You”, in particular:

>As McDermott says, “The whole problem is getting the hearer to notice what it has been told. Not ‘understand,’ but ‘notice.’ ” Suppose that instead the physicist told you, “Light is made of little curvy things.” Would you notice any difference of anticipated experience?

>How can you realize that you shouldn’t trust your seeming knowledge that “light is waves”? One test you could apply is asking, “Could I regenerate this knowledge if it were somehow deleted from my mind?”

https://www.lesswrong.com/posts/fg9fXrHpeaDD6pEPL/truly-part...