As i wrote this quote down, i had a feeling that it was for us. So when we first came in this class, we had the same ideas of what infinity was: endless, boundless, uncountable, incomprehensible, etc (the attribute list). As we learned more about the views and the sizes of infinity, about how to use one-to-one correspondences and the power sets to discover it, about philosophical problems with infinity, our "doors of perception" seem more opened.
After we got our first papers back and were assigned to be responsible for the final paper, professor Hamman explained some of the reading Escher on Escher. Next, he questioned if anybody ever related infinity with music. Some said yes and some said no. Then an argument came up between the answer: Is silence a sound? Again, some said yes some said no. Somebody on the Yes side basically mentioned that we see color because our mind can detect the wave radiation from light. If there's no light, the color is black. So black is a color. Using the same argument, we may say that the lack of sound (silence) is still perceived as a sound. But people one the No side argued that silence is independent. It is not created by anybody/anything so it's not a sound.
Then, we discussed how different it is when there's sound under water. The really high pitch of the whale was an example. We also talked about how fun and weird it is when we can make bubbles if we try to talk/breathe under water. After that, somehow, we ended up with what Escher said: "Infinity cannot be portrayed by sound."
Professor introduced us to the works of Ivars Peterson, a mathematician and computer writer.