David H Wolpert in Aeon:
Despite his many intellectual achievements, I suspect there are some concepts my dog cannot conceive of, or even contemplate. He can sit on command and fetch a ball, but I suspect that he cannot imagine that the metal can containing his food is made from processed rocks. I suspect he cannot imagine that the slowly lengthening white lines in the sky are produced by machines also made from rocks like his cans of dog food. I suspect he cannot imagine that these flying repurposed dog food cans in the sky look so small only because they are so high up. And I wonder: is there any way that my dog could know that these ideas even exist? It doesn’t take long for this question to spread elsewhere. Soon I start to wonder about concepts that I don’t know exist: concepts whose existence I can never even suspect, let alone contemplate. What can I ever know about that which lies beyond the limits of what I can even imagine?
Attempting to answer this question only leads us to more questions. In this essay, I’m going to run through a sequence of 10 queries that provide insight into how we might begin conceiving of what’s at stake in such a question and how to answer it – and there is much at stake.
More here.