#764 “This Instant!”

Dr. craig’s response

Hooray for your father! I fully agree! It’s evident from the comparison with spatial points that by a “moment” he understands a temporal instant, a durationless point in time. (I usually distinguish moments from instants as having a non-zero, finite duration, but this difference is merely terminological.) I agree completely that temporal instants are merely conceptualizations, the result of treating time as akin to a geometrical line. Since points and instants have no non-zero extension, it is impossible that a collection of them should add up to a positive distance. Thus we should not think of a line as a composition of points. The case of time is even more interesting: since between any two instants there is always another instant, it is impossible for there to be consecutive instants. So if there really were a present instant, it could not have a successor. But that contradicts the fact of temporal becoming.

You ask, “If time can be represented as a ray, is a moment really an aspect of real time?” No; a ray is a line with a beginning point and a direction, and as such is another mathematical conceptualization of time. It is, as you say, a representation of time. So the instants of time which the ray comprises should not be thought of as real. So “Is ‘the present moment [instant]’ a coherent concept?” Yes, it’s a logically coherent concept, but we should not think that any such thing exists in reality. It’s just a mathematical device.

You can read more about this fascinating subject in my book Time and Eternity:  Exploring God’s Relationship to Time (Wheaton, Ill.:  Crossway, 2001), in the section on “The Myth of Passage.”