More often than the feeling that time is passing quickly is for me the sense that time, as a passage, has constricted and become a narrow tube or tunnel. “I have no time” means then that I have no room to do other things than run down this tunnel; I can’t stop, go left or right, relax, do something else.
Today I was lying on the couch listening to some music and watching some afternoon clouds go by, and I wondered what it would be like if I never had to work, if I had no obligations to fulfil. The narrow tunnel would become a round, spacious, vaulted room, and all would be stillness. Time would still pass quickly — perhaps even more quickly now that I wasn’t thinking about it — and death would still come when it would. But now the speeding train would have no windows, and the landscape would never change. If I may mix my metaphors.
Which reminds me of a brilliant essay/convocation address I once read in Harpers by Joseph Brodsky. I’ll dig it up some time soon, when the tunnel widens out a bit.