Take this book as an example, why does it have a thickness? Because many sheets of paper are stacked together. In the same way, even though a flower petal and a sheet of paper are very thin, their thickness is also comprised of countless dust particles or quarks. This thickness is formed by minute particles arranged in order from front to back. When the needle tip pierces the thin sheet of paper, our eyes cannot see the needle tip pass through these particles in that order. This shows that our eyes are unable to see the true nature of matter at all.

- Quote from The Four Seals of Dhama, "The Practice of Realizing Emptiness"