Jumping from past to present
miseri
When reading an article about classes for children with learning
difficulties, I came across this sentence:
“…after the class, all children understood that the world is
round…”
I might be mistaken here, but the sentence jumps from the past tense
‘understood’ to present tense ‘is’ and seems to jar. I understand
that things that are ‘fact’ are in the present tense, but is it right
in this context?
Cheers
James Hogg
> Hi All
>
> When reading an article about classes for children with learning
> difficulties, I came across this sentence:
>
> round��
>
> I might be mistaken here, but the sentence jumps from the past tense
> that things that are �fact� are in the present tense, but is it right
> in this context?
Yes.
Not all rules about sequence of tenses work properly in the real world.
--
James
miseri
>
> Yes.
>
> Not all rules about sequence of tenses work properly in the real world.
>
> --
> James
Thank you, James
Nick
> miseri wrote:
>> Hi All
>>
>> When reading an article about classes for children with learning
>> difficulties, I came across this sentence:
>>
>> “…after the class, all children understood that the world is
>> round…”
>>
>> I might be mistaken here, but the sentence jumps from the past tense
>> ‘understood’ to present tense ‘is’ and seems to jar. I understand
>> that things that are ‘fact’ are in the present tense, but is it right
>> in this context?
>
> Yes.
>
> Not all rules about sequence of tenses work properly in the real world.
Particularly, the fact that the world is round is ongoing, but the
understanding took place at a particular time.
It's just the same as "Isaac Newton discovered that gravity is a
universal force"
--
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development version: http://canalplan.eu
Prai Jei
> Particularly, the fact that the world is round is ongoing, but the
> understanding took place at a particular time.
>
> It's just the same as "Isaac Newton discovered that gravity is a
> universal force"
In a discussion about the gradual slowdown of the Earth's spin, I set the
following poser as an exercise for the reader:
"Show that both past and future eclipses are displaced eastwards from where
they would occur on the basis of a constant-spinning Earth."
I justified the use of the present passive ("are displaced") on the basis
that knowledge of the *schedule* of past and future eclipses is ongoing,
although the eclipses themselves took place / will take place at particular
times.
--
ξ:) Proud to be curly
Interchange the alphabetic letter groups to reply
Mark Brader
>>> "...after the class, all children understood that the world is
>>> round..."
Nick Atty writes:
> Particularly, the fact that the world is round is ongoing, but the
> understanding took place at a particular time.
>
> It's just the same as "Isaac Newton discovered that gravity is a
> universal force"
Yes. And in both sentences, "was" would also be correct. It was
true then, it is still true, and there's no reason to believe it's
changed.
If it might have changed since they learned it, *then* you would have
to use "was".
--
Mark Brader I'm not pompous; I'm pedantic.
Toronto Let me explain it to you.
m...@vex.net --Mary Kay Kare
My text in this article is in the public domain.
Joe Fineman
Fowler (MEU s.v. Sequence of tenses) calls this the "vivid sequence"
and says that it is "abnormal but often preferable". It seems to me
(slightly) preferable here.
--
--- Joe Fineman jo...@verizon.net
||: Competence makes more enemies than incompetence. :||
Peter Moylan
> James Hogg <Jas....@gOUTmail.com> writes:
>
>> miseri wrote:
>>> Hi All
>>>
>>> When reading an article about classes for children with learning
>>> difficulties, I came across this sentence:
>>>
>>> “…after the class, all children understood that the world is
>>> round…”
>>>
>>> I might be mistaken here, but the sentence jumps from the past tense
>>> ‘understood’ to present tense ‘is’ and seems to jar. I understand
>>> that things that are ‘fact’ are in the present tense, but is it right
>>> in this context?
>> Yes.
>>
>> Not all rules about sequence of tenses work properly in the real world.
>
> Particularly, the fact that the world is round is ongoing, but the
> understanding took place at a particular time.
>
> It's just the same as "Isaac Newton discovered that gravity is a
> universal force"
Was he justified in assuming that physical laws wouldn't change after
his death? That's a pretty big mental leap.
--
Peter Moylan, Newcastle, NSW, Australia. http://www.pmoylan.org
For an e-mail address, see my web page.
Eric Walker
Yes. The matter is straightforward: the present tense is (as you say
used to express propositions that are "general truths": two and two
*make* four; the world *is* round; honesty *is* the best policy; &c &c.
For specific truths, the casting would be different: “…after the class,
all children understood that Columbus *discovered* America [thus proving
that the world *is* round]…”
Incidentally, what happened to the definite article before "children"?
--
Cordially,
Eric Walker, Owlcroft House
http://owlcroft.com/english/
John O'Flaherty
<pvstownse...@ntlworld.com> wrote:
>Nick set the following eddies spiralling through the space-time continuum:
>
>> Particularly, the fact that the world is round is ongoing, but the
>> understanding took place at a particular time.
>>
>> It's just the same as "Isaac Newton discovered that gravity is a
>> universal force"
>
>In a discussion about the gradual slowdown of the Earth's spin, I set the
>following poser as an exercise for the reader:
>
>"Show that both past and future eclipses are displaced eastwards from where
>they would occur on the basis of a constant-spinning Earth."
Changing the subject, why is that the case?
>I justified the use of the present passive ("are displaced") on the basis
>that knowledge of the *schedule* of past and future eclipses is ongoing,
>although the eclipses themselves took place / will take place at particular
>times.
--
John
Prai Jei
continuum:
>>"Show that both past and future eclipses are displaced eastwards from
>>where they would occur on the basis of a constant-spinning Earth."
>
> Changing the subject, why is that the case?
Because the displacement is proportional to the *square* of the time
difference between now and the time of the eclipse. The displacement is
thus in the same direction for both past and future.
Imagine a time-lapse image of the solar system running for a couple of
thousand years to a point when an eclipse is scheduled. Because the earth's
spin is slowing down, it hasn't turned quite so much as expected. The areas
of the earth then in daylight are to the east of the "expected" position.
Now start again at the present, and run backwards for a couple of thousand
years to a past eclipse. The earth is spinning backwards and is speeding
up, so when we reach the past eclipse point the earth has spun backwards
rather too much, again with the result that the areas of the earth then in
daylight are to the east of the "expected" position.
History records several instances where a battle was in progress as an
eclipse occurred, whereupon the combatants, taking the eclipse as a sign of
the gods' displeasure, immediately made peace. It was through attempts to
correlate these with the eclipse schedule drawn up from the laws of
physics, that led to discovery of the slowdown of the earth's spin in the
first place.
"Every day seems a little longer" - Buddy Holly
And it is - by an average of 40 nanoseconds relative to the previous day.
Insignificant except for high-precision scientific measurements,
insignificant within a human lifetime, but over many millennia the effects
add up. Suppose that, 2000 years ago, an absolutely accurate clock had been
set up, synchronised to the length of the day as it was then, and running
perfectly without adjustment ever since. It would now be seen to be running
fast - by about 1 second every month. Still insignificant - even good
quartz clocks of today seldom achieve that accuracy.
But of course it would also be showing the wrong time. Have a guess how far
it would be adrift.
<rot13> Guerr ubhef naq gjragl zvahgrf nurnq. </rot13>
John Varela
<pvstownse...@ntlworld.com> wrote:
> Suppose that, 2000 years ago, an absolutely accurate clock had been
> set up, synchronised to the length of the day as it was then, and running
> perfectly without adjustment ever since. It would now be seen to be running
> fast - by about 1 second every month.
A second a month? So next month it will be one more second fast
than it is today?
--
John Varela
Trade NEWlamps for OLDlamps for email
Prai Jei
continuum:
> On Wed, 4 Nov 2009 18:36:51 UTC, Prai Jei
> <pvstownse...@ntlworld.com> wrote:
>
>> Suppose that, 2000 years ago, an absolutely accurate clock had been
>> set up, synchronised to the length of the day as it was then, and running
>> perfectly without adjustment ever since. It would now be seen to be
>> running fast - by about 1 second every month.
>
> A second a month? So next month it will be one more second fast
> than it is today?
Yes you got it, 'cos all those 40 nanoseconds per day per day (note the
units!) over 2000 years have added up to making the day longer by 1/30
second than it was 2000 years ago.
The perceived error in the speed of the clock is roughly proportional to the
elapsed time, so in another 2000 years' time it will be gaining two seconds
a month, but the error in the displayed time goes as the *square* of
elapsed time so it will then be at least thirteen hours fast.
John O'Flaherty
So, using the sum of an arithetic progression with a difference of 40
ns/day, maintained over 2000 years of 365.25 days:
2000*365.25*(2000*365.25-1)*4e-8sec / 2 ~= 10672.6 sec., or 2.96 hrs,
or 2 hours and 58 minutes. Your answer was 3 hrs 20 minutes. What did
I do wrong?
--
John
Peter Moylan
> History records several instances where a battle was in progress as an
> eclipse occurred, whereupon the combatants, taking the eclipse as a sign of
> the gods' displeasure, immediately made peace. It was through attempts to
> correlate these with the eclipse schedule drawn up from the laws of
> physics, that led to discovery of the slowdown of the earth's spin in the
> first place.
>
> "Every day seems a little longer" - Buddy Holly
>
> And it is - by an average of 40 nanoseconds relative to the previous day.
I'd been wondering why my body clock seemed to be out of kilter.
Prai Jei
It's not an arithmetic progression for the display because the error in the
displayed time goes as the square of elapsed time.
The 40 nanoseconds per day per day deceleration can be taken as constant
over the timescale involved, but in reality it too is slowing down since
the actual slowdown of the earth's spin is going to be closer to
exponential.
Since the deceleration can be taken as constant, the speed error is going to
vary linearly, and the display error is going to vary quadratically, as
time passes.
When the clock was set up it was running accurately. 2000 years later it is
gaining a second a month, and this is the bit that can be taken to be
linear. That's an average of half a second a month for 2000 years. 24000
months, so that's 12000 seconds = 3 hours 20 minutes error in the display.
Hairy Monster
> Prai Jei wrote:
>
>> History records several instances where a battle was in progress as an
>> eclipse occurred, whereupon the combatants, taking the eclipse as a sign
>> of
>> the gods' displeasure, immediately made peace. It was through attempts
>> to correlate these with the eclipse schedule drawn up from the laws of
>> physics, that led to discovery of the slowdown of the earth's spin in the
>> first place.
>>
>> "Every day seems a little longer" - Buddy Holly
>>
>> And it is - by an average of 40 nanoseconds relative to the previous day.
>
> I'd been wondering why my body clock seemed to be out of kilter.
You been drinking?
--
<unknown> has caused an error in <unknown>. <unknown> will now close.
Peter Moylan
Worse: I stopped drinking.
John O'Flaherty
<pvstownse...@ntlworld.com> wrote:
The sum of an arithmetic progression is almost a simple square too,
for a large number of terms, as you can see from the formula above. It
should be correct if the change is taken as linear. Anyhow, it's only
an 11% error.
>The 40 nanoseconds per day per day deceleration can be taken as constant
>over the timescale involved, but in reality it too is slowing down since
>the actual slowdown of the earth's spin is going to be closer to
>exponential.
>
>Since the deceleration can be taken as constant, the speed error is going to
>vary linearly, and the display error is going to vary quadratically, as
>time passes.
>
>When the clock was set up it was running accurately. 2000 years later it is
>gaining a second a month, and this is the bit that can be taken to be
>linear. That's an average of half a second a month for 2000 years. 24000
>months, so that's 12000 seconds = 3 hours 20 minutes error in the display.
Well, at any rate, it's fascinating,as was your original riddle. Why
is the earth slowing?
--
John
Nick Spalding
on Fri, 06 Nov 2009 09:40:46 -0600:
> Well, at any rate, it's fascinating,as was your original riddle. Why
> is the earth slowing?
Something to do with the energy expended in making the tides.
--
Nick Spalding
BrE/IrE
Peter Duncanson (BrE)
wrote:
This effect, Tidal Friction, is described briefly at:
http://www.physics.mcgill.ca/~crawford/PSG/PSG11/204_97_L11.9_tidfric.html
and at greater length at:
http://www.synapses.co.uk/astro/moon1.html
and at:
http://bowie.gsfc.nasa.gov/ggfc/tides/intro.html
and in Wikipedia:
http://en.wikipedia.org/wiki/Tidal_acceleration
--
Peter Duncanson, UK
(in alt.usage.english)