The present is not part of time. Have you ever thought about it? How long is the present?
The past has a duration, the future has a duration. What is the duration of the present?
How long does it last? Between the past and the future can you measure the present? It is immeasurable; it is almost not. It is not time at all: it is the penetration of eternity into time.
And Zen lives in the present. The whole teaching is: how to be in the present, how to get out of the past which is no more and how not to get involved in the future which is not yet, and just to be rooted, centered, in that which is.