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Old 22-07-2020, 07:53 AM posted to uk.rec.gardening
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On 21/07/2020 21:22, Vir Campestris wrote:
On 21/07/2020 19:20, The Natural Philosopher wrote:
How many angels will fir on the head of a pin?


Which debate sounds less silly when you find out that the debate was not
over 10 or 100 or some such, but over finite vs infinite.

Andy


Indeed. Which is what string theory is. A way to counteract the
mathematical problems of 'point sources of mass' leading to infinite
gravitational fields, in the limit. Amongst other things.


--
"Corbyn talks about equality, justice, opportunity, health care, peace,
community, compassion, investment, security, housing...."
"What kind of person is not interested in those things?"

"Jeremy Corbyn?"


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Old 22-07-2020, 01:53 PM posted to uk.rec.gardening
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On Tue, 21 Jul 2020 13:20:29 -0000 (UTC), (Nick
Maclaren) wrote:

In article ,
AnthonyL wrote:

When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists. If there is not
a proof there that satisfies all then shut up and go seek it".

It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".


The former shows your misunderstanding of complex issues - why do you
think there IS a single, explicable, complete answer? There very
often isn't - and, in some cases, there are questions that are quite
simply unanswerable in such terms.


So they may as well believe in a god and argue about that? They may
theorise one thing and it is in pursuit of theories that more becomes
known but to argue that one belief is better than another is the
anathama of what I understand science to be. What's the point in
believe a heavy stone will fall to the ground faster because it is
heavy?

And the second is effectively ********. You cannot design for all
possible events - ships are designed only against (say) 'once in
a millennium' storms, not the worst possible storm, let alone such
things as Cumbre Viejo or the Storegga shelf collapsing.


That is not how engineering builds in safety factors. At least not in
the aviation (airframe and engine) environment I started off in.


--
AnthonyL

Why do scientists need to BELIEVE in anything?
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Old 22-07-2020, 03:24 PM posted to uk.rec.gardening
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On 22/07/2020 12:53, AnthonyL wrote:
On Tue, 21 Jul 2020 13:20:29 -0000 (UTC), (Nick
Maclaren) wrote:

In article ,
AnthonyL wrote:

When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists. If there is not
a proof there that satisfies all then shut up and go seek it".

It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".


The former shows your misunderstanding of complex issues - why do you
think there IS a single, explicable, complete answer? There very
often isn't - and, in some cases, there are questions that are quite
simply unanswerable in such terms.


So they may as well believe in a god and argue about that? They may
theorise one thing and it is in pursuit of theories that more becomes
known but to argue that one belief is better than another is the
anathama of what I understand science to be. What's the point in
believe a heavy stone will fall to the ground faster because it is
heavy?


You need to make a fine distinction here.

All real world knowledge is essentially *inductive* propositions. (what
Sherlock Holmes called wrongly 'deduction')


Inductive knowledge is the art of proposing causes (assuming causality
exists and is valid) from effects = Phenomena. Shit on the carpet? The
dog did it. Or the Russians.

If it ended there, one proposition would be as good as the other, BUT
the point about *science* is you take a DNA test and if its canine and
matches the pooch, then the probability that the dog did it is very high.

And that is the point about *science*. Its *inductive* propositions can
create *deductive* propositions that *can be tested*.

IF 'the dog did it' THEN the DNA will match. IF 'gravity' works as
Newton suggested THEN planetary orbits will be...what they are,
approximately anyway. (Einstein etc).

Religion however is 'IF GOD then...well...' nothing. Or everything. It's
all *untestable* and therefore not a *scientific* proposition. Might be
true, might not. Can't tell. No WAY to tell.

And the second is effectively ********. You cannot design for all
possible events - ships are designed only against (say) 'once in
a millennium' storms, not the worst possible storm, let alone such
things as Cumbre Viejo or the Storegga shelf collapsing.


That is not how engineering builds in safety factors. At least not in
the aviation (airframe and engine) environment I started off in.


Oh I think it is. Airframes are stressed to - for example - -2g to +4g
for a commercial aircraft. At some level that represents a 'once every
thousand year' event. A microprocessor might very well be likely to fail
from a timing issue once every ten years, but from cosmic ray impact
once every 3 months.. safety margins consist in building to meet the
unlikely knowns. Not the unknowns of which one is ignorant though.

If anybody has actually seriously said 'make sure your skyscraper can
withstand a 300 tonne aeroplane full of fuel impacting at 300mph' the
twin towers would still be standing...

As it was the 45 minute fire rating did its job and should have allowed
time to evacuate...if there had been any way to get people above the
fire out.


--
"The great thing about Glasgow is that if there's a nuclear attack it'll
look exactly the same afterwards."

Billy Connolly
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Old 22-07-2020, 03:48 PM posted to uk.rec.gardening
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On 22/07/2020 12:53, AnthonyL wrote:
On Tue, 21 Jul 2020 13:20:29 -0000 (UTC), (Nick
Maclaren) wrote:

In article ,
AnthonyL wrote:

When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists. If there is not
a proof there that satisfies all then shut up and go seek it".

It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".


The former shows your misunderstanding of complex issues - why do you
think there IS a single, explicable, complete answer? There very
often isn't - and, in some cases, there are questions that are quite
simply unanswerable in such terms.


So they may as well believe in a god and argue about that? They may
theorise one thing and it is in pursuit of theories that more becomes
known but to argue that one belief is better than another is the
anathama of what I understand science to be. What's the point in


Science is a progressive approximation to describing reality using the
best mathematics available. The more a scientific theory can explain and
the more experimental tests of its predictions that do not refute it the
stronger that scientific belief in that theory becomes.

The fundamental conservation laws are close to being an immutable core
set of beliefs and firmly believed by all as anything in physics.

But there is always a possibility that some clever experiment done
tomorrow will refute something that until now has been considered a
sacrosanct law of physics. Groundbreaking experiments with unexpected
results tend to break open whole new areas of physics for study.

Radioactivity, superconductivity, general relativity, lasers for
instance. You can never tell in advance what will be important.

Each advance in physics includes all the existing results as some weak
field limiting case of a more complete and complicated theory. It is
still not known if a grand unified theory of everything is even
possible. Certain pure mathematical proofs hint that it may not be.

believe a heavy stone will fall to the ground faster because it is
heavy?


Allowing for air resistance it does fall ever so slightly faster. But
shape will make a big difference too. Experiment trumps elegant theory
every time - nature is the final arbiter of every scientific theory.

A flat plate will fall more slowly than a sphere. Shape really matters
unless you do the experiment in a vacuum.

And the second is effectively ********. You cannot design for all
possible events - ships are designed only against (say) 'once in
a millennium' storms, not the worst possible storm, let alone such
things as Cumbre Viejo or the Storegga shelf collapsing.


That is not how engineering builds in safety factors. At least not in
the aviation (airframe and engine) environment I started off in.


They do basically look for the worst case loading that the airframe
might be expected to encounter in service and then choose a suitable
multiple of that as a safety margin. Victorians tended to err on the
side of caution with a factor of 7 so their sewers still work whereas
the cheap and nasty blocks of flats built in the 1960's used a safety
factor of 1.0 which is why Ronan Point collapsed like a deck of cards.

--
Regards,
Martin Brown
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Old 22-07-2020, 07:08 PM posted to uk.rec.gardening
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AnthonyL wrote:
Why do scientists need to BELIEVE in anything?


Very interesting question: the short answer is they don't, except they
need to at least sort of believe the 'evidence of their senses', and the
basic structure they impose on the Universe -
space-time/matter/energy/causality etc are all useful *assumptions*, but
are metaphysical - unprovable - in nature.


When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists. If there is not
a proof there that satisfies all then shut up and go seek it".


Debating or discussing with each other -- the loaded "arguing" is
rarely the appropriate word -- is quite a good way of finding out
what the differences really are, whether or not one's position
needs adjustment, or what steps might be taken to clarify or
prove the thing one way or another.

I not infrequently disagree with my colleagues, since we not only
have different backgrounds, different expertise, and often different
intuitions; the resulting debate is not only instructive but productive.


#Paul


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Old 22-07-2020, 11:42 PM posted to uk.rec.gardening
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On 22/07/2020 18:08, #Paul wrote:
AnthonyL wrote:
Why do scientists need to BELIEVE in anything?

Very interesting question: the short answer is they don't, except they
need to at least sort of believe the 'evidence of their senses', and the
basic structure they impose on the Universe -
space-time/matter/energy/causality etc are all useful *assumptions*, but
are metaphysical - unprovable - in nature.


When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists. If there is not
a proof there that satisfies all then shut up and go seek it".


Debating or discussing with each other -- the loaded "arguing" is
rarely the appropriate word -- is quite a good way of finding out
what the differences really are, whether or not one's position
needs adjustment, or what steps might be taken to clarify or
prove the thing one way or another.


Arguing can sometimes be the right word. Fred Hoyle's disparaging use of
the term "Big Bang" Cosmology to describe the new theory that supplanted
his own Steady State Universe model for instance. It didn't help that
some of the early observational radio telescope surveys that made steady
state untenable was partly contaminated with ghost sources in sidelobes.

When cosmic microwave background was observed by Bell Labs the case for
Big Bang was essentially water tight but adherents to Steady State never
gave in. They fought a rear guard action pretty much to the last man.

I not infrequently disagree with my colleagues, since we not only
have different backgrounds, different expertise, and often different
intuitions; the resulting debate is not only instructive but productive.


When big egos get involved things can get ugly even in science.

A sadder case was the poor unfortunate Russian scientist who found the
first self catalysing redox clock reaction that flew in the face of
normal chemical theory as it was known at the time. Unable to get it
published other than in an obscure Russian journal he eventually gave up
working as a scientist and never lived to see it become world famous in
the 1970's. He was unlucky and well ahead of his time.

https://en.wikipedia.org/wiki/Belous...insky_reaction

Wegeners continental drift was another good idea that was ridiculed at
first but ultimately the mass of evidence overwhelmed his critics.

https://ucmp.berkeley.edu/history/wegener.html

--
Regards,
Martin Brown
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Old 23-07-2020, 03:38 AM posted to uk.rec.gardening
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On 22/07/2020 14:48, Martin Brown wrote:
On 22/07/2020 12:53, AnthonyL wrote:
On Tue, 21 Jul 2020 13:20:29 -0000 (UTC), (Nick
Maclaren) wrote:

In article ,
AnthonyL wrote:

When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists.¬* If there is not
a proof there that satisfies all then shut up and go seek it".

It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".

The former shows your misunderstanding of complex issues - why do you
think there IS a single, explicable, complete answer?¬* There very
often isn't - and, in some cases, there are questions that are quite
simply unanswerable in such terms.


So they may as well believe in a god and argue about that?¬* They may
theorise one thing and it is in pursuit of theories that more becomes
known but to argue that one belief is better than another is the
anathama of what I understand science to be.¬* What's the point in


Science is a progressive approximation to describing reality using the
best mathematics available. The more a scientific theory can explain and
the more experimental tests of its predictions that do not refute it the
stronger that scientific belief in that theory becomes.


I slightly object to 'belief' in that context. I think the phrase used
is 'strong evidence' The material realists believe that the fact that
sciences *works* is 'strong evidence' that the entities that comprise
its theories - e.g. gravity - 'actually exist'.
P prefer to merely note that they are simply explanations that give
useful predictions without ascribing any truth content to them at all.

As can be seen with e.g. Einsetein where a radical different
construction - bent space time, gives almost the same result in most
cases and a far better result in a few cases.

The fundamental conservation laws are close to being an immutable core
set of beliefs and firmly believed by all as anything in physics.
#

As is causality. But what 'causes' that particular radioactive element
to decay at that particular time? Quanatum level mess cannot be solved
by simple cause and effect, instead we have a probability function only.

Einstein claimed he could not believe that God played dice..but that is
a belief, only.

But there is always a possibility that some clever experiment done
tomorrow will refute something that until now has been considered a
sacrosanct law of physics. Groundbreaking experiments with unexpected
results tend to break open whole new areas of physics for study.

Indeed. That pesky photoelectric effect that led to quantum physics,
which gave us the semiconductor and the laser..

Radioactivity, superconductivity, general relativity, lasers for
instance. You can never tell in advance what will be important.

Yup. Or where it all might lead. First integrated circuits were to
control guided missiles. Now they run twitter.

Each advance in physics includes all the existing results as some weak
field limiting case of a more complete and complicated theory. It is
still not known if a grand unified theory of everything is even
possible. Certain pure mathematical proofs hint that it may not be.

If you take Gödel and view him as Hofstatder does as an example of
*recursion*, then it becomes clear that a given knowledge base can never
use itself to prove its own correctness.

Inductive propositions about the real world made by limited beings can
never be sure to have captured the world either completely or
truthfully. See the Matrix. absent the Red Pill how could you tell you
were in a simulation?

Science is not about truth, it is about effective prediction of the
future. Using models of reality that can never shown to be correct. only
be shown to be incorrect.


believe a heavy stone will fall to the ground faster because it is
heavy?


Allowing for air resistance it does fall ever so slightly faster. But
shape will make a big difference too. Experiment trumps elegant theory
every time - nature is the final arbiter of every scientific theory.

That's why it was calld ahem! NATURAL PHILOSOPHY

A flat plate will fall more slowly than a sphere. Shape really matters
unless you do the experiment in a vacuum.

And the second is effectively ********.¬* You cannot design for all
possible events - ships are designed only against (say) 'once in
a millennium' storms, not the worst possible storm, let alone such
things as Cumbre Viejo or the Storegga shelf collapsing.


That is not how engineering builds in safety factors.¬* At least not in
the aviation (airframe and engine) environment I started off in.


They do basically look for the worst case loading that the airframe
might be expected to encounter in service and then choose a suitable
multiple of that as a safety margin. Victorians tended to err on the
side of caution with a factor of 7 so their sewers still work whereas
the cheap and nasty blocks of flats built in the 1960's used a safety
factor of 1.0 which is why Ronan Point collapsed like a deck of cards.

No, to be fair progressive collapse, like the Comet and metal fatigue,
was sort of known about but not considered something you should take
into account.

Same goes for various resonant bridge collapses - Tacoma narrows?

We live, and we learn from thee failures, that there is more we need to
take into account. Known unknowns become known knowns.


But, the problem with science is that fact that it has always worked
before is no absolute guarantee it will work in the future. As the man
falling past the 30th floor replied when asked how he was doing 'okay,
so far' is all we can really know. Assuming that memory is real and
what just happened is not a figment of our imagination, and we are not
trapped in a timeless present with nothing but false memories....

Ultimately we nothing for sure, just a bunch of ideas that seem to have
worked, so far, enough for us to to the Darwinian Shag and beget another
round of brats ...


....Until woke came along and now no one knows whether or not they ought
to not actually be gay, or so full of guilt for actually having the
temerity to exist, that instant suicide is indicated out of pure shame.

All one can say is that such genes will not then be passed on...

--
The lifetime of any political organisation is about three years before
its been subverted by the people it tried to warn you about.

Anon.
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Old 23-07-2020, 03:42 AM posted to uk.rec.gardening
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On 22/07/2020 22:42, Martin Brown wrote:
On 22/07/2020 18:08, #Paul wrote:
AnthonyL wrote:
Why do scientists need to BELIEVE in anything?

Very interesting question: the short answer is they don't, except they
need to at least sort of believe the 'evidence of their senses', and
the
basic structure they impose on the Universe -
space-time/matter/energy/causality etc are all useful *assumptions*,
but
are metaphysical - unprovable - in nature.


When I hear them arguing and disagreeing with eachother the thought
that immediately comes to me is "You are scientists.¬* If there is not
a proof there that satisfies all then shut up and go seek it".


Debating or discussing with each other -- the loaded "arguing" is
rarely the appropriate word -- is quite a good way of finding out
what the differences really are, whether or not one's position
needs adjustment, or what steps might be taken to clarify or
prove the thing one way or another.


Arguing can sometimes be the right word. Fred Hoyle's disparaging use of
the term "Big Bang" Cosmology to describe the new theory that supplanted
his own Steady State Universe model for instance. It didn't help that
some of the early observational radio telescope surveys that made steady
state untenable was partly contaminated with ghost sources in sidelobes.

When cosmic microwave background was observed by Bell Labs the case for
Big Bang was essentially water tight but adherents to Steady State never
gave in. They fought a rear guard action pretty much to the last man.

I not infrequently disagree with my colleagues, since we not only
have different backgrounds, different expertise, and often different
intuitions; the resulting debate is not only instructive but productive.


When big egos get involved things can get ugly even in science.

A sadder case was the poor unfortunate Russian scientist who found the
first self catalysing redox clock reaction that flew in the face of
normal chemical theory as it was known at the time. Unable to get it
published other than in an obscure Russian journal he eventually gave up
working as a scientist and never lived to see it become world famous in
the 1970's. He was unlucky and well ahead of his time.

https://en.wikipedia.org/wiki/Belous...insky_reaction

Wegeners continental drift was another good idea that was ridiculed at
first but ultimately the mass of evidence overwhelmed his critics.

https://ucmp.berkeley.edu/history/wegener.html

On the other foot we have Lysenkoism, phrenology, Eugenics, Racial
theory, Piltdown Man and Climate Change, all massively popular theories
because they fitted a particular social and political narrative, that
turned out to be utter bunk...

--
Any fool can believe in principles - and most of them do!


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Old 23-07-2020, 12:16 PM posted to uk.rec.gardening
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In article ,
AnthonyL wrote:

It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".


The former shows your misunderstanding of complex issues - why do you
think there IS a single, explicable, complete answer? There very
often isn't - and, in some cases, there are questions that are quite
simply unanswerable in such terms.


So they may as well believe in a god and argue about that? They may
theorise one thing and it is in pursuit of theories that more becomes
known but to argue that one belief is better than another is the
anathama of what I understand science to be. What's the point in
believe a heavy stone will fall to the ground faster because it is
heavy?


When you are in a hole, stop digging. I was polite, and said
"misunderstanding", but the correct term is "wilful ignorance".
For an explanation, look on BBC catchup for Sir Paul Nurse's
explanation to the COVID Science Committee (or some such title),
a couple of nights back.

And the second is effectively ********. You cannot design for all
possible events - ships are designed only against (say) 'once in
a millennium' storms, not the worst possible storm, let alone such
things as Cumbre Viejo or the Storegga shelf collapsing.


That is not how engineering builds in safety factors. At least not in
the aviation (airframe and engine) environment I started off in.


Oh, yes, it is, and I have worked with and for some of those people.
Here are two examples:

Aircraft regularly drop hundreds of feet in clear air turbulence,
and are designed to survive that, but vortices are unlimited in
size and they are NOT designed to survive a drop of (say) 2,000
metres.

Engines are designed to survive moderate bird strike and hail, but
are NOT designed to survive complete flocks of geese or head-sized
hail.

Unknown factors (and the chances of such incidents ARE unknown,
because there is not enough data to estimate them) are the reason
that safety factors are needed in those cases.


Regards,
Nick Maclaren.
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Old 23-07-2020, 01:47 PM posted to uk.rec.gardening
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On Tue, 21 Jul 2020 13:56:57 +0100, The Natural Philosopher
wrote:

On 21/07/2020 12:49, AnthonyL wrote:
On Mon, 20 Jul 2020 17:27:28 +0100, The Natural Philosopher
wrote:




It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".


Sounds ******** to me. Safety factor is the margin to known problems.
Says nothing about unknown problems, but how could it?


https://en.wikipedia.org/wiki/Factor_of_safety
or more precisely the "Margin of safety"

That has nothing to do with unknown problems and has everything to do
with the uncertainty of the anticipated behaviour of the materials in
question.

Albeit a long time ago I also spent a lot of time calculating (before
ready access to calculators) Mean Time Before Failure and Operational
Reliability of sub-systems in an engine.

No doubt any safety factor applied nowadays would be much more refined
than in those days as the manufacturing and build processes improved
and the ignorance factor decreased.

--
AnthonyL

Why do scientists need to BELIEVE in anything?


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Old 23-07-2020, 03:29 PM posted to uk.rec.gardening
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On 23/07/2020 02:42, The Natural Philosopher wrote:
On 22/07/2020 22:42, Martin Brown wrote:


A sadder case was the poor unfortunate Russian scientist who found the
first self catalysing redox clock reaction that flew in the face of
normal chemical theory as it was known at the time. Unable to get it
published other than in an obscure Russian journal he eventually gave
up working as a scientist and never lived to see it become world
famous in the 1970's. He was unlucky and well ahead of his time.

https://en.wikipedia.org/wiki/Belous...insky_reaction

Wegeners continental drift was another good idea that was ridiculed at
first but ultimately the mass of evidence overwhelmed his critics.

https://ucmp.berkeley.edu/history/wegener.html

On the other foot we have Lysenkoism, phrenology, Eugenics, Racial
theory, Piltdown Man and Climate Change, all massively popular theories
because they fitted a particular social and political narrative, that
turned out to be utter bunk...


Climate change deniers are invariably working for fossil fuel companies
and using exactly the same doubt and uncertainty tactics as they did to
keep the dumb punters smoking tobacco. You only have to follow the money
to see which side is science and which is utter bunkum "supported" by
deniers for hire working for various US rightwing "think tanks".

The rest of them I agree with you are pure anti-science.

Though it is beginning to look like there is a race based genetic
component to susceptibility to novel coronavirus Covid-19. It could be
as simple as having a dark skin at high latitude or being a sickle cell
anaemia carrier but it may well be something more subtle from way back.

The recent genomic sequencing paper suggests that one risk factor comes
from our Neanderthal ancestors through a variation on gene 3.

https://www.biorxiv.org/content/10.1...07.03.186296v1

Whereas pure homo sapiens directly from Africa does not have this.

https://www.biorxiv.org/content/10.1...07.03.186296v1

It is the first working hypothesis that more or less correlates with the
observed death rates experienced in various countries around the globe.

The other is ABO blood group related and seems to be confirmed now that
having any A antibodies is bad for you and being blood group O is best.

--
Regards,
Martin Brown
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Old 24-07-2020, 08:29 PM posted to uk.rec.gardening
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On 23/07/2020 12:47, AnthonyL wrote:
On Tue, 21 Jul 2020 13:56:57 +0100, The Natural Philosopher
wrote:

On 21/07/2020 12:49, AnthonyL wrote:
On Mon, 20 Jul 2020 17:27:28 +0100, The Natural Philosopher
wrote:




It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".


Sounds ******** to me. Safety factor is the margin to known problems.
Says nothing about unknown problems, but how could it?


https://en.wikipedia.org/wiki/Factor_of_safety
or more precisely the "Margin of safety"

That has nothing to do with unknown problems and has everything to do
with the uncertainty of the anticipated behaviour of the materials in
question.

Ignorance === unknown.

I didnt start the use of that term, I merely replied that 'ignorance
factor' implied 'margin for unknownn (problems)

Albeit a long time ago I also spent a lot of time calculating (before
ready access to calculators) Mean Time Before Failure and Operational
Reliability of sub-systems in an engine.

No doubt any safety factor applied nowadays would be much more refined
than in those days as the manufacturing and build processes improved
and the ignorance factor decreased.

What 'ignorance factor'?

You have categorically stated that this has nothing top do with unknown
problems, therefore there is no 'ignorance factor



--
In todays liberal progressive conflict-free education system, everyone
gets full Marx.
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Old 24-07-2020, 09:18 PM posted to uk.rec.gardening
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On 23/07/2020 14:29, Martin Brown wrote:
On 23/07/2020 02:42, The Natural Philosopher wrote:
On 22/07/2020 22:42, Martin Brown wrote:


A sadder case was the poor unfortunate Russian scientist who found
the first self catalysing redox clock reaction that flew in the face
of normal chemical theory as it was known at the time. Unable to get
it published other than in an obscure Russian journal he eventually
gave up working as a scientist and never lived to see it become world
famous in the 1970's. He was unlucky and well ahead of his time.

https://en.wikipedia.org/wiki/Belous...insky_reaction

Wegeners continental drift was another good idea that was ridiculed
at first but ultimately the mass of evidence overwhelmed his critics.

https://ucmp.berkeley.edu/history/wegener.html

On the other foot we have Lysenkoism, phrenology, Eugenics, Racial
theory, Piltdown Man and Climate Change, all massively popular
theories because they fitted a particular social and political
narrative, that turned out to be utter bunk...


Climate change deniers are invariably working for fossil fuel companies
and using exactly the same doubt and uncertainty tactics as they did to
keep the dumb punters smoking tobacco.


Indeed. Al Gore and the NYT are using exactrlyt these tactics to deny
the science - which basically proves that climate change is nothing to
do with CO2 - in order to increase the price and government control of
energy and benefit the fossil fuel companies - Al Gore was working fror
Enron and trying to promote gas over coal as Enron had serious gas
interests at that time when he made 'an inconvenient truth' - which
was, of course, actually a really convenient lie.

You only have to follow the money
to see which side is science and which is utter bunkum "supported" by
deniers for hire working for various US rightwing "think tanks".


Precisely so. The renewable industry and climate change in general is a
multi trillion dollar industry now based on utterly bogus 'science'.
CO2 has been rising monotonically since the 1960s, but climate change
more or less stopped in the year 2000, and certainly hasn't been rising
monotonically since, despite all the attempts to 'correct' the data to
make it so. Ergo the core assumption that all or the vast majority of
late 20th century warming is due to CO2 is refuted utterly and
completely. The real denial is by those who refuse to face these facts
and maintain that CO2 is teh major and on;y important 'cause' of
temperature change, when the geological record shows that actually
climate change is the major cause of rising CO2 levels as the oceans
outgas...and it wasn't burning fossil fuels that led to the end of the
'little ice age',and nor is the recorded fact of vineyards in Denmark
and Sweden in the Roman warm period indicative of it being 'warmer than
all recorded history' now...nor are records of the 1912 (or was in 1920)
ice free North West passage indicative that Arctic ice has never been
this low, nor is it a convenient truth that there are more polar bears
in the Arctic than at any time in recorded memory...

There is a huge conspiracy to deny the reality of climate change, but it
is coming from the Left and from people making trillions out of energy

And you are part of it - just another 'useful idiot; who drunk their
koolaid.

There are of course no 'right wing think tanks' - it's another
invention of climate change fraudsters



The rest of them I agree with you are pure anti-science.

Though it is beginning to look like there is a race based genetic
component to susceptibility to novel coronavirus Covid-19. It could be
as simple as having a dark skin at high latitude or being a sickle cell
anaemia carrier but it may well be something more subtle from way back.


Golly, a closet racist?~

The recent genomic sequencing paper suggests that one risk factor comes
from our Neanderthal ancestors through a variation on gene 3.

https://www.biorxiv.org/content/10.1...07.03.186296v1

Whereas pure homo sapiens directly from Africa does not have this.

https://www.biorxiv.org/content/10.1...07.03.186296v1

It is the first working hypothesis that more or less correlates with the
observed death rates experienced in various countries around the globe.

The other is ABO blood group related and seems to be confirmed now that
having any A antibodies is bad for you and being blood group O is best.



--
If I had all the money I've spent on drink...
...I'd spend it on drink.

Sir Henry (at Rawlinson's End)
  #29   Report Post  
Old 25-07-2020, 01:56 PM posted to uk.rec.gardening
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On Fri, 24 Jul 2020 19:29:46 +0100, The Natural Philosopher
wrote:

On 23/07/2020 12:47, AnthonyL wrote:
On Tue, 21 Jul 2020 13:56:57 +0100, The Natural Philosopher
wrote:

On 21/07/2020 12:49, AnthonyL wrote:
On Mon, 20 Jul 2020 17:27:28 +0100, The Natural Philosopher
wrote:




It somewhat reminds me of what I learnt as an engineer "Safety factor
is simply ignorance factor".

Sounds ******** to me. Safety factor is the margin to known problems.
Says nothing about unknown problems, but how could it?


https://en.wikipedia.org/wiki/Factor_of_safety
or more precisely the "Margin of safety"

That has nothing to do with unknown problems and has everything to do
with the uncertainty of the anticipated behaviour of the materials in
question.

Ignorance === unknown.

I didnt start the use of that term, I merely replied that 'ignorance
factor' implied 'margin for unknownn (problems)

Albeit a long time ago I also spent a lot of time calculating (before
ready access to calculators) Mean Time Before Failure and Operational
Reliability of sub-systems in an engine.

No doubt any safety factor applied nowadays would be much more refined
than in those days as the manufacturing and build processes improved
and the ignorance factor decreased.

What 'ignorance factor'?

You have categorically stated that this has nothing top do with unknown
problems, therefore there is no 'ignorance factor



The ignorance factor is the uncertainty in the reliability of the test
measurements taken against any sample, it has nothing to do with
unknown outside influences.

The tensile strength of Steel, structural ASTM A36 steel is
250MPa. Well exactly? All? Most samples? If you're life depended
on it would you apply that load and feel safe? Would design engineers
be prepared to put their reputation on that figure? Or might you
calculate everything at 230MPa just to give you a margin of safety
because you want to be sure (ie because you are not sure)?

These are not external unknown problems which is the way I had
interpreted some of the criticism of my statement. If a plane crashed
into a building that was reliant on the 250MPa structural frame that
is beyond the design criteria. If the plane crashed because a wing
failed because a bolt snapped because it had no safety margin built
into the design then that smacks of overconfidence/negligence and a
slight application of extra material would have saved the day if the
designer had understood that the full behaviour of the bolt was not
exactly understood, ie ignorance factor as cited to me many years ago.


--
AnthonyL

Why do scientists need to BELIEVE in anything?
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Old 05-08-2020, 02:32 PM posted to uk.rec.gardening
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Posts: 3
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Martin Brown wrote:
Climate change [...]


Here's a recent review, which the many experts on the subject
here will have no trouble at all understanding :-)


The Physics of Climate Variability and Climate Change

Michael Ghil, Valerio Lucarini

The climate system is a forced, dissipative, nonlinear, complex and
heterogeneous system that is out of thermodynamic equilibrium. The system
exhibits natural variability on many scales of motion, in time as well as
space, and it is subject to various external forcings, ...

https://arxiv.org/abs/1910.00583
https://doi.org/10.1103/RevModPhys.92.035002


Summary here (but the summary is not the science):
https://physics.aps.org/articles/v13/121


#Paul


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