# Semi Deep Thought
**URL:** https://boards.straightdope.com/t/semi-deep-thought/765996
**Category:** Miscellaneous and Personal Stuff I Must Share
**Created:** [September 15, 2016, 10:57am UTC](https://boards.straightdope.com/t/semi-deep-thought/765996 "2016-09-15T10:57:35Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@rstrats](https://boards.straightdope.com/u/rstrats)
#### Post date: [September 15, 2016, 10:57am UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/1 "2016-09-15T10:57:35Z")
I wonder how long the present lasts before it becomes the past?
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### Author:  [@jtur88](https://boards.straightdope.com/u/jtur88)
#### Post date: [September 15, 2016, 11:03am UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/2 "2016-09-15T11:03:57Z")
Not very long.
There is an interesting mind experiment. The present is a dimensionless interface between the past and the future, so its linear magnitude is zero, and the present does not therefore exist. The past is only recollections, and the future only expectations, which also have no tangible existence, so nothing exists.
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### Author:  [@thirdname](https://boards.straightdope.com/u/thirdname)
#### Post date: [September 15, 2016, 12:37pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/3 "2016-09-15T12:37:59Z")
Until the Langoliers eat it.
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### Author:  [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)
#### Post date: [September 15, 2016, 12:42pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/4 "2016-09-15T12:42:51Z")
Long enough for you to write that OP. But no longer.
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### Author:  [@elbows](https://boards.straightdope.com/u/elbows)
#### Post date: [September 15, 2016, 1:34pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/5 "2016-09-15T13:34:50Z")
But a fleeting moment…it is already the past!
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### Author:  [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)
#### Post date: [September 15, 2016, 3:58pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/6 "2016-09-15T15:58:31Z")
Until the next present is opened.
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### Author:  [@Leaffan](https://boards.straightdope.com/u/Leaffan)
#### Post date: [September 15, 2016, 4:01pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/7 "2016-09-15T16:01:44Z")
The present lasts forever. It is always the present.
ETA: The past and the future are merely man-made constructs: the past can’t be changed and the future can’t be predicted.
(The future’s uncertain and the end is always near. Baby.)
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### Author:  [@Chefguy](https://boards.straightdope.com/u/Chefguy)
#### Post date: [September 15, 2016, 4:15pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/8 "2016-09-15T16:15:38Z")
> [@](#):
>
> Greetings, my friends! We are all interested in the future, for that is where you and I are going to spend the rest of our lives. And remember my friends; future events such as these will affect you in the future.
- The Amazing Criswell
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### Author:  [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)
#### Post date: [September 15, 2016, 4:17pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/9 "2016-09-15T16:17:17Z")
_You’re older than you’ve ever been,
And now you’re even older,
And now you’re even older,
And now you’re even older_
-They Might Be Giants
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### Author:  [@Blaster\_Master](https://boards.straightdope.com/u/Blaster_Master)
#### Post date: [September 15, 2016, 4:27pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/10 "2016-09-15T16:27:19Z")
I think it depends on which theory of time you subscribe to. If you’re an A-theorist, that means, like several said, that the present is all that exists, it is an instant of zero duration, or effectively so (maybe duration of one unit of Planck time? I’m not a physicist). However, if you’re a B-theorist, present doesn’t have much meaning, as all moments in time are equally real, they’re just coordinates in a 4-dimensional space-time, and similarly, past and future are just relative to whatever given point one is examining. And, so, in that sense, the present always exists.
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### Author:  [@ftg](https://boards.straightdope.com/u/ftg)
#### Post date: [September 15, 2016, 4:43pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/11 "2016-09-15T16:43:12Z")
You are actually living in the past. What your consciousness “sees” as the present is what actually happened about a half second ago.
[Not Gertrude Stein]There is no “now” now.[/Not Gertrude Stein]
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### Author:  [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)
#### Post date: [September 15, 2016, 5:34pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/12 "2016-09-15T17:34:05Z")
Half-remembered quote: “The past is gone. The future is not yet here. We have only the now.”
And, to be contrary: “The past is gone. The present vanishes as it appears. There is only the future.”
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### Author:  [@Doctor\_Jackson](https://boards.straightdope.com/u/Doctor_Jackson)
#### Post date: [September 15, 2016, 6:26pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/13 "2016-09-15T18:26:17Z")
I was once given a candy bar for my birthday. I ate it just after lunch. The next morning I pooped. It took, therefore, about 18 hours for the present to become the passed.
YTMV (Your Timing May Vary)
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### Author:  [@BubbaDog](https://boards.straightdope.com/u/BubbaDog)
#### Post date: [September 15, 2016, 7:35pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/14 "2016-09-15T19:35:18Z")
Considering the physical lag between the time our sense organs receive information and the time we comprehend that information…we are always living in the past.
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### Author:  [@ftg](https://boards.straightdope.com/u/ftg)
#### Post date: [September 15, 2016, 7:50pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/15 "2016-09-15T19:50:48Z")
> [@BubbaDog](#):
>
> Considering the physical lag between the time our sense organs receive information and the time we comprehend that information…we are always living in the past.
Apparently some Dopers are living about 3 hours in the [past](http://boards.straightdope.com/sdmb/showpost.php?p=19630452&postcount=11).
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### Author:  [@Quartz](https://boards.straightdope.com/u/Quartz)
#### Post date: [September 15, 2016, 11:09pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/16 "2016-09-15T23:09:33Z")
> [@rstrats](#):
>
> I wonder how long the present lasts before it becomes the past?
1.
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### Author:  [@Fool\_in\_the\_Rain](https://boards.straightdope.com/u/Fool_in_the_Rain)
#### Post date: [September 16, 2016, 4:01pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/17 "2016-09-16T16:01:37Z")
[George Carlin on time](https://www.youtube.com/watch?v=fNG_DzyDzp4)
“There’s no present. There’s only the immediate future and the recent past.”
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### Author:  [@TreacherousCretin](https://boards.straightdope.com/u/TreacherousCretin)
#### Post date: [September 16, 2016, 5:42pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/18 "2016-09-16T17:42:01Z")
“There is no present or future; only the past, happening over and over again, right now.” (Eugene O’Neill)
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### Author:  [@eschereal](https://boards.straightdope.com/u/eschereal)
#### Post date: [September 16, 2016, 6:17pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/19 "2016-09-16T18:17:57Z")
The present is that moment in which time fails to keep everything from happening at once.
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### Author:  [@Pabitel](https://boards.straightdope.com/u/Pabitel)
#### Post date: [September 16, 2016, 7:36pm UTC](https://boards.straightdope.com/t/semi-deep-thought/765996/20 "2016-09-16T19:36:52Z")
[The present doesn’t exist](http://www.pbs.org/wgbh/nova/blogs/physics/2014/06/there-is-no-now/). It is an illusion.