73. What is time? Strictly speaking, it is a mere concept
which does not exist in an absolute sense.
On the
other hand what space is to matter, time is to mind.
Conventionally we speak of past (atãta), present
(paccuppanna), and future (anàgata).
Past is defined as that which has gone beyond its own
state or the moments of genesis, development, and cessation
(attano sabhàvaü uppàdàdikkhaõaü và atãtà atikkantà
atãtà).
Present is that which on account of this and that reason
enters, goes, exists above the moments of genesis etc.
(taü taü kàraõaü pañicca uppàdàdikkhaõaü uddhaü
pannà, gatà, pavattà == paccuppannà).
Future is that which has not yet reached both states
(tadubhayam’ pi na àgatà sampattà).
According to Abhidhamma each consciousness consists
of three phases—uppàda (genesis), ñhiti (development),
and bhaïga (dissolution or cessation). In the view
of some commentators there is no intermediate ñhiti stage
but only the stages of arising and passing away. Each
thought-moment is followed by another. Time is thus the
sine qua non of the succession of mental states. The fundamental
unit of time is the duration of a thought-moment.
Commentators say that the rapidity of these fleeting
thought-moments is such that within the brief duration of
a flash of lightning there may be billions of thoughtmoments.
Matter, which also constantly changes, endures only
for seventeen thought-moments, being the time duration
for one thought-process.
Past is gone. Future has not come. We live only for
one thought-moment and that slips into the irrevocable
past. In one sense there is only the eternal now. In another
sense the so-called present is the transitional stage
from the future to the past.
The Dictionary of Philosophy defines time “as the
general medium in which all events take place in succession
or appear to take place in succession”.
Atthasàlinã states that time is a concept derived from
this or that phenomenon. And it does not exist by nature,
it is merely a concept. (Taü taü upàdàya pa¤¤atto kàlo
nàma. So pan’ esa sabhàvato avijjamànattà pa¤¤attimattako
pAGE 215
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