IS Forum
Forum Index Register Members List Events Mark Forums Read Help

Go Back   International Skeptics Forum » General Topics » Science, Mathematics, Medicine, and Technology
 


Welcome to the International Skeptics Forum, where we discuss skepticism, critical thinking, the paranormal and science in a friendly but lively way. You are currently viewing the forum as a guest, which means you are missing out on discussing matters that are of interest to you. Please consider registering so you can gain full use of the forum features and interact with other Members. Registration is simple, fast and free! Click here to register today.
Reply
Old 2nd March 2021, 07:43 PM   #41
theprestige
Penultimate Amazing
 
Join Date: Aug 2007
Location: Hong Kong
Posts: 50,504
Originally Posted by Thor 2 View Post
Well it would seem others here seem to have an inkling of what I am about.

Nice conciliatory approach too imply I am ignorant by the way.

Try researching how trees manage to pump water from their roots to their leaves, and you will get lots of nonsense and impressive sounding terms, but no clear explanation. Well not an explanation that will satisfy someone with a rudimentary knowledge of physics anyway.
Why would someone with a mere rudimentary understanding of physics think they were entitled to a clear explanation of tree biology? Is that what's got your panties in a bunch? Tree experts aren't bothering to explain their mastery on yourself novice level?
theprestige is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 2nd March 2021, 07:49 PM   #42
Sideroxylon
Featherless biped
 
Sideroxylon's Avatar
 
Join Date: Aug 2008
Location: Aporia
Posts: 24,436
Originally Posted by WhatRoughBeast View Post
It's only a tautology if only poppies possess a Somnolent Nature.

If there exists a class of objects which possess a Somnolent Nature, then it can be asserted (and makes sense, although it's not strictly speaking implied) that such a Nature is causal. Then explaining the effects of poppies as an example of a larger force at work is not a tautology,
Looks like a clear tautology in the context of, “Why does opium cause sleepiness?” Is there any new information here? That there exists some causal nature in opium is implied in the question, while sleep inducing and somnolent are synonyms.

The answer certainly seems unsatisfactory as an explanation. If not for being tautological, why does it fail?

Last edited by Sideroxylon; 2nd March 2021 at 08:04 PM.
Sideroxylon is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 05:03 PM   #43
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by theprestige View Post
Why would someone with a mere rudimentary understanding of physics think they were entitled to a clear explanation of tree biology? Is that what's got your panties in a bunch? Tree experts aren't bothering to explain their mastery on yourself novice level?

Why theprestige you excel yourself with the insults yet again.*

The mechanisms used in tree biology must obey the laws of physics. The explanations I see from these experts don't appear to show a knowledge of physics. I see suggestions that trees suck up water. Suck up water over a hight of many many metres which would require a vacuum of many atmospheres. This is impossible don't you know? Perhaps not, maybe your knowledge of physics is not so good.

Incidentally I have a good friend who is an agricultural scientist. The question has him stumped.

* When you don't have an argument I guess that is all you can do.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 05:18 PM   #44
EHocking
Philosopher
 
EHocking's Avatar
 
Join Date: Apr 2004
Posts: 8,592
Originally Posted by Thor 2 View Post
Why theprestige you excel yourself with the insults yet again.*

The mechanisms used in tree biology must obey the laws of physics. The explanations I see from these experts don't appear to show a knowledge of physics. I see suggestions that trees suck up water. Suck up water over a hight of many many metres which would require a vacuum of many atmospheres. This is impossible don't you know? Perhaps not, maybe your knowledge of physics is not so good.

Incidentally I have a good friend who is an agricultural scientist. The question has him stumped.

* When you don't have an argument I guess that is all you can do.
This should help you understand that a vacuum of many atmospheres is not required to move water up a tree.
The key is the very small diameter of the xylum.

https://www.scientificamerican.com/a...-trees-such-a/
__________________
"A closed mouth gathers no feet"
"Ignorance is a renewable resource" P.J.O'Rourke
"It's all god's handiwork, there's little quality control applied", Fox26 reporter on Texas granite
You can't make up anything anymore. The world itself is a satire. All you're doing is recording it. Art Buchwald
EHocking is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 05:23 PM   #45
gnome
Penultimate Amazing
 
gnome's Avatar
 
Join Date: Aug 2001
Posts: 11,247
"Because then everyone will want that."

Not always an invalid explanation, if it's obvious why everyone availing themselves is a bad idea. But if that's not clear, it makes a frustrating answer.
__________________

gnome is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 06:02 PM   #46
EHocking
Philosopher
 
EHocking's Avatar
 
Join Date: Apr 2004
Posts: 8,592
Originally Posted by gnome View Post
"Because then everyone will want that."
YouTube Video This video is not hosted by the ISF. The ISF can not be held responsible for the suitability or legality of this material. By clicking the link below you agree to view content from an external website.
I AGREE
__________________
"A closed mouth gathers no feet"
"Ignorance is a renewable resource" P.J.O'Rourke
"It's all god's handiwork, there's little quality control applied", Fox26 reporter on Texas granite
You can't make up anything anymore. The world itself is a satire. All you're doing is recording it. Art Buchwald
EHocking is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 06:06 PM   #47
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by EHocking View Post
This should help you understand that a vacuum of many atmospheres is not required to move water up a tree.
The key is the very small diameter of the xylum.

https://www.scientificamerican.com/a...-trees-such-a/
Thanks for the input EHocking but I have seen this article, or something similar, before. Look at this excerpt:


Quote:
This pulling of water, or tension, that occurs in the xylem of the leaf, will extend all the way down through the rest of the xylem column of the tree and into the xylem of the roots due to the cohesive forces holding together the water molecules along the sides of the xylem tubing. (Remember, the xylem is a continuous water column that extends from the leaf to the roots.) Finally, the negative water pressure that occurs in the roots will result in an increase of water uptake from the soil.

I call this a typical explanation that isn't. Or it is if you are happy that many atmospheres of vacuum can be created. Perhaps the answer does lie in here somewhere if the water is drawn up in stages but the above talks of a continuous water column.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 06:22 PM   #48
EHocking
Philosopher
 
EHocking's Avatar
 
Join Date: Apr 2004
Posts: 8,592
Originally Posted by Thor 2 View Post
Thanks for the input EHocking but I have seen this article, or something similar, before. Look at this excerpt:

I call this a typical explanation that isn't. Or it is if you are happy that many atmospheres of vacuum can be created. Perhaps the answer does lie in here somewhere if the water is drawn up in stages but the above talks of a continuous water column.
Many atmospheres are not created nor are they necessary.
There are many, many resources at your fingertips to help you understand the explanation, e.g.,
Look up cohesion tension theory.
https://en.wikipedia.org/wiki/Xylem#...tension_theory

It can 'splain it to you, but it can't understand it for you.
__________________
"A closed mouth gathers no feet"
"Ignorance is a renewable resource" P.J.O'Rourke
"It's all god's handiwork, there's little quality control applied", Fox26 reporter on Texas granite
You can't make up anything anymore. The world itself is a satire. All you're doing is recording it. Art Buchwald
EHocking is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 06:31 PM   #49
Gord_in_Toronto
Penultimate Amazing
 
Gord_in_Toronto's Avatar
 
Join Date: Jul 2006
Posts: 20,572
Originally Posted by Thor 2 View Post
Thanks for the input EHocking but I have seen this article, or something similar, before. Look at this excerpt:

Quote:
This pulling of water, or tension, that occurs in the xylem of the leaf, will extend all the way down through the rest of the xylem column of the tree and into the xylem of the roots due to the cohesive forces holding together the water molecules along the sides of the xylem tubing. (Remember, the xylem is a continuous water column that extends from the leaf to the roots.) Finally, the negative water pressure that occurs in the roots will result in an increase of water uptake from the soil.
I call this a typical explanation that isn't. Or it is if you are happy that many atmospheres of vacuum can be created. Perhaps the answer does lie in here somewhere if the water is drawn up in stages but the above talks of a continuous water column.
From a cursory glace at what's highlighted, it looks like the water is maybe pumped up the tree from the bottom. Not sucked from the top. I would also hazard a guess that this is not the only physical principle involved. Surface tension as well, maybe? Osmosis?
__________________
"Reality is what's left when you cease to believe." Philip K. Dick
Gord_in_Toronto is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 06:32 PM   #50
Gord_in_Toronto
Penultimate Amazing
 
Gord_in_Toronto's Avatar
 
Join Date: Jul 2006
Posts: 20,572
Originally Posted by Gord_in_Toronto View Post
From a cursory glace at what's highlighted, it looks like the water is maybe pumped up the tree from the bottom. Not sucked from the top. I would also hazard a guess that this is not the only physical principle involved. Surface tension as well, maybe? Osmosis?
Just a WAG. I'm not a botanist.
__________________
"Reality is what's left when you cease to believe." Philip K. Dick
Gord_in_Toronto is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 06:34 PM   #51
EHocking
Philosopher
 
EHocking's Avatar
 
Join Date: Apr 2004
Posts: 8,592
Originally Posted by Gord_in_Toronto View Post
From a cursory glace at what's highlighted, it looks like the water is maybe pumped up the tree from the bottom. Not sucked from the top. I would also hazard a guess that this is not the only physical principle involved. Surface tension as well, maybe? Osmosis?
It is both pushed and pulled.

See my link above
__________________
"A closed mouth gathers no feet"
"Ignorance is a renewable resource" P.J.O'Rourke
"It's all god's handiwork, there's little quality control applied", Fox26 reporter on Texas granite
You can't make up anything anymore. The world itself is a satire. All you're doing is recording it. Art Buchwald
EHocking is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 11:20 PM   #52
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by EHocking View Post
Many atmospheres are not created nor are they necessary.
There are many, many resources at your fingertips to help you understand the explanation, e.g.,
Look up cohesion tension theory.
https://en.wikipedia.org/wiki/Xylem#...tension_theory

It can 'splain it to you, but it can't understand it for you.

Thanks again. This is probably one of the most honest articles I have seen on the subject. See the following:

Quote:
Over the past century, there has been a great deal of research regarding the mechanism of xylem sap transport; today, most plant scientists continue to agree that the cohesion-tension theory best explains this process, but multiforce theories that hypothesize several alternative mechanisms have been suggested, including longitudinal cellular and xylem osmotic pressure gradients, axial potential gradients in the vessels, and gel- and gas-bubble-supported interfacial gradients.[26][27]

You see the above. They are still hypothesising about the subject, and yet you will find articles where some will say it is still this or that with absolute confidence. They throw in words like osmosis and capillary action etc but no detail about how it happens.

Any scientist will also ask the question: "Where and how does the energy come from to do the work?" I know they will just throw at you "It comes from the Sun", but no detail is given about the mechanism.

If the mechanism was so well understood then why can't we copy it. Lots of water needs pumping.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 11:24 PM   #53
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by Gord_in_Toronto View Post
From a cursory glace at what's highlighted, it looks like the water is maybe pumped up the tree from the bottom. Not sucked from the top. I would also hazard a guess that this is not the only physical principle involved. Surface tension as well, maybe? Osmosis?

Surface tension or capillary action and osmosis are tiny forces.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 11:26 PM   #54
EHocking
Philosopher
 
EHocking's Avatar
 
Join Date: Apr 2004
Posts: 8,592
Originally Posted by Thor 2 View Post
Thanks again. This is probably one of the most honest articles I have seen on the subject. See the following:




You see the above. They are still hypothesising about the subject, and yet you will find articles where some will say it is still this or that with absolute confidence. They throw in words like osmosis and capillary action etc but no detail about how it happens.

Any scientist will also ask the question: "Where and how does the energy come from to do the work?" I know they will just throw at you "It comes from the Sun", but no detail is given about the mechanism.

If the mechanism was so well understood then why can't we copy it. Lots of water needs pumping.
The sun -> evaporation at stomata-> cohesive tension.

Rather than do this piecemeal it would be more advantageous to you to read an article on the entire process.

You not understanding how osmosis or capillary action is relevant is not the authors issue IMO.
__________________
"A closed mouth gathers no feet"
"Ignorance is a renewable resource" P.J.O'Rourke
"It's all god's handiwork, there's little quality control applied", Fox26 reporter on Texas granite
You can't make up anything anymore. The world itself is a satire. All you're doing is recording it. Art Buchwald
EHocking is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 11:29 PM   #55
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
What I am trying to point out here is that many, when asked a technical, or other, question, will just throw in some impressive sounding words and walk away. Many, such as theprestige, will be satisfied. I am not.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 11:36 PM   #56
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by EHocking View Post
The sun -> evaporation at stomata-> cohesive tension.

Rather than do this piecemeal it would be more advantageous to you to read an article on the entire process.

You not understanding how osmosis or capillary action is relevant is not the authors issue IMO.

I am familiar with osmosis and capillary action, but they are tiny forces.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 3rd March 2021, 11:41 PM   #57
Sideroxylon
Featherless biped
 
Sideroxylon's Avatar
 
Join Date: Aug 2008
Location: Aporia
Posts: 24,436
Originally Posted by Thor 2 View Post
What I am trying to point out here is that many, when asked a technical, or other, question, will just throw in some impressive sounding words and walk away. Many, such as theprestige, will be satisfied. I am not.
Sounds like a lot of cynicism going on.
Sideroxylon is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 4th March 2021, 12:18 AM   #58
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by Sideroxylon View Post
Sounds like a lot of cynicism going on.

Oh yes! Lots of it.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 4th March 2021, 07:42 AM   #59
Gord_in_Toronto
Penultimate Amazing
 
Gord_in_Toronto's Avatar
 
Join Date: Jul 2006
Posts: 20,572
Originally Posted by Thor 2 View Post
I am familiar with osmosis and capillary action, but they are tiny forces.
Maybe, but that us not to say that their effects cannot be cumulative.
__________________
"Reality is what's left when you cease to believe." Philip K. Dick
Gord_in_Toronto is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 4th March 2021, 02:18 PM   #60
Thor 2
Philosopher
 
Thor 2's Avatar
 
Join Date: May 2016
Location: Brisbane, Aust.
Posts: 6,684
Originally Posted by Gord_in_Toronto View Post
Maybe, but that us not to say that their effects cannot be cumulative.

Possibly but hard to imagine.

Osmotic pressure being the pressure difference between waters with different salinity (in this case), if we try to imagine it happening in stages, then somehow the water must loose its salinity so that it can be drawn up again to a more saline mixture.
__________________
Thinking is a faith hazard.
Thor 2 is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 4th March 2021, 04:14 PM   #61
Sideroxylon
Featherless biped
 
Sideroxylon's Avatar
 
Join Date: Aug 2008
Location: Aporia
Posts: 24,436
Personal incredulity plus cynicism seems a heady mix.
Sideroxylon is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 4th March 2021, 04:17 PM   #62
EHocking
Philosopher
 
EHocking's Avatar
 
Join Date: Apr 2004
Posts: 8,592
Originally Posted by Thor 2 View Post
Possibly but hard to imagine.

Osmotic pressure being the pressure difference between waters with different salinity (in this case), if we try to imagine it happening in stages, then somehow the water must loose its salinity so that it can be drawn up again to a more saline mixture.
Sorry - just because you cannot imagine it, and prefer to believe that the water column requires multiple atmospheres of pressure to overcome, does not make the explanation invalid.
The question was not whether you believe it or not, but that it was explained sufficiently to understand.

You are now arguing that you don't like the explanation, not that the explanation was not clear, e.g., your complaint in the OP was
"when questioned about some technical issue, will just throw an impressive sounding line at you, and think they have provided an explanation"
Again, your inability to accept or understand the current example is not becuase of someone throwing an impressive line at you, it is because you do not understand the science behind the explanation, so just dismiss it as it being "an impressive sounding line [thrown] at you".

If you had followed the reference link attached to the explanation
"Xylem transport is driven by a combination[29] of transpirational pull from above and root pressure from below..."
You would get your answer to what transpirational pull and root pressure really are - not what you find "hard to imagine".
https://www.nature.com/scitable/know...ants-103016037

It is unreasonable to dismiss the explanation as "an impressive sounding line" because you do not understand, or accept, the underlying scientific basics of the explanation.
__________________
"A closed mouth gathers no feet"
"Ignorance is a renewable resource" P.J.O'Rourke
"It's all god's handiwork, there's little quality control applied", Fox26 reporter on Texas granite
You can't make up anything anymore. The world itself is a satire. All you're doing is recording it. Art Buchwald
EHocking is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 4th March 2021, 05:12 PM   #63
Sideroxylon
Featherless biped
 
Sideroxylon's Avatar
 
Join Date: Aug 2008
Location: Aporia
Posts: 24,436
We see a lot of this sort of thing from creationists, homeopaths, psychics etc.

“Scientific knowledge is pretence and explanations fail to pass the sniff test.” This to make room for ideas that fail scientific scrutiny.
Sideroxylon is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Reply

International Skeptics Forum » General Topics » Science, Mathematics, Medicine, and Technology

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -7. The time now is 07:11 AM.
Powered by vBulletin. Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.

This forum began as part of the James Randi Education Foundation (JREF). However, the forum now exists as
an independent entity with no affiliation with or endorsement by the JREF, including the section in reference to "JREF" topics.

Disclaimer: Messages posted in the Forum are solely the opinion of their authors.