We exist only in the present, and we need to learn to live in the present. We can’t affect the past, and we have no way of knowing what effect we may have on the future. We need to do our living today, concentrate on the present moment — on doing the next right thing — and let the future take care of itself. If we are always thinking about tomorrow, next week, next year — the next raise, romance, promotion or what have you, we are unlikely to do well at work, love, or life in general.
Every change we make in our lives affects the future, sometimes in big ways, and sometimes in small ones. I can’t know whether failing to buy new shoelaces today will result in a dangerous fall tomorrow.