This question reminds me of a phrase in Derrida's Heidegger: The Question of Being & History, (pages 180-181) where time is referred to as nothing, but also that which is produced by the motion of the mind.
To clarify what he calls Kant’s “obscure assertion” that “time affects
a concept, in particular, the concept of the representations of
objects” (Kant and the Problem of Metaphysics, 133), Heidegger shows
what time as pure intuition must signify: originarily, it can in no
way signify affection of something by something, affection of a being
by another being, affection of an existing subject by something
outside it: because time is nothing, as such it cannot affect
anything. It is affection of self by self. Auto-affection, a concept
that is as incomprehensible as is, in truth, the movement of
temporalization. This auto-affection as temporality is not a
characteristic affecting transcendental subjectivity, one of its
attributes; it is, on the contrary, that starting from which the self,
the Selbst, the I think constitutes itself and announces itself to
itself. Heidegger writes, [French] p. 244:
As pure self-affection, time is not an acting affection that strikes a
self which is at hand (vorhandenes Selbst). Instead, as pure it
forms the essence (Wesen) of something like self-activating
(Sich-selbst-angehen as self-relating, to relate to self,
angegangen werden zu können). However, if it belongs to the essence of the finite subject to be able to be activated as a self,
then time
as pure self-affection forms the essential structure of subjectivity.
Only on the grounds of this self-hood can the finite creature be what
it must be: dependent upon taking things in stride (angewiesen auf
Hinnahme). (Kant and the Problem of Metaphysics, 132)
This form of time would be primordial, authentic time, not ordinary time. Some elucidation here: Heidegger's Being and Time, part 8: Temporality, by Simon Critchley in The Guardian (2009).
Re. "we do not understand or appreciate its true meaning or purpose in life."
Critchley:
I can make a decision to take over the fact of who I am in an action. This is what Heidegger calls "resoluteness".
... the present is something that I can seize hold of and resolutely make my own [in] "the moment of vision."
This is the value of time: to becomes self-activated, rather than a passenger in life. Also, activity in the moment of vision yields the value of time, but it is part & parcel with the self. The value of a determination of experience in the synthesis of future and past cannot be separated from the being who enacts it.
