As mentioned earlier, the Buddha said an instant denotes the time it takes a needle tip to pass through a very thin flower petal, but this instant can be divided into still smaller parts. If an instant can be separated into hundred thousands of time segments, we can imagine how short any one time segment is. Yet, even in this fraction of an instant, everything is in a state of flux. The Buddhist term for this is arising and ceasing, the modern term is motion.

- Quote from The Four Seals of Dhama, "The Practice of Impermanence"