We need to be aware that everything in this world is illusory and insubstantial. What really exists and the nature of this world is "one ten thousandth of a second". A "moment" can be one hundred thousandth of a second or even shorter, but let's not make it complicated -- we can just take one ten thousandth of a second as the present moment. If we can seize the present moment, then the past and future world do not exist because the past has gone, and the future has not yet been born. What really exists is the "one ten thousandth of a second"; that is our world.

-- Khenpo Tsultrim Lodro Rinpoche