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jubeh
12-27-2011, 01:16 AM
I found this wiki page and its p addictive.

http://en.wikipedia.org/wiki/List_of_common_misconceptions

If you know of any common misconceptions that aren't on there feel free to post them.

Bacon_Barbarian
12-27-2011, 01:26 AM
Donald Trump

Hayashida
12-28-2011, 12:25 AM
good post, bacon

Bacon_Barbarian
12-28-2011, 01:51 AM
Inorite?

jubeh
12-28-2011, 01:55 AM
Going to start posting interesting ones that I think people still subscribe to.


The word "crap" did not originate as a back-formation of British plumber Thomas Crapper's surname, nor does his name originate from the word "crap", although the surname may have helped popularize the word


Contrary to popular belief, dogs do not sweat by salivating. It is not true that dogs do not have sweat glands or have sweat glands only on their tongues. They do sweat, mainly through the footpads. However, dogs do primarily regulate their body temperature through panting.


The idea that lightning never strikes the same place twice is one of the oldest and most well-known superstitions about lightning. There is no reason that lightning would not be able to strike the same place twice; if there is a thunderstorm in a given area, then objects and places which are more prominent or conductive (and therefore minimize distance) are more likely to be struck. For instance, lightning strikes the Empire State Building in New York City about 100 times per year.


People do not use only ten percent of their brains.

Delphinus
12-28-2011, 09:54 AM
Normally only really stupid people bring up the 'ten percent of their brains' thing. The best reply is 'maybe you do'.

Fenn
12-28-2011, 03:32 PM
There is no evidence that Vikings wore horns on their helmets.[9] In fact, the image of the horned helmet stems from the scenography of an 1876 production of the Der Ring des Nibelungen opera cycle by Richard Wagner.[10] The actual Viking helmets were practical battle gear, and had a rather plain appearance.

Depressing.


Contrary to a widespread perception, the real number 0.999...—where the decimal point is followed by an infinite sequence of nines—is exactly equal to 1.[297] They are two different ways of writing the same real number.[298] A 2009 study by Weller et al.[299] states that "Tall and Schwarzenberger (1978) asked first year university mathematics students whether 0.999... is equal to 1. The majority of the students thought that 0.999... is less than 1." Weller et al. go on to describe their own controlled experiment, performed "during the 2005 fall semester at a major research university in the southern United States. Pre-service elementary and middle school teachers from all five sections of a sophomore-level mathematics content course on number and operation participated in the study. [...] On the question of whether .999...=1, 72% of the control group and 83% of the experimental group expressed their view that .999... is not equal to 1."

What.

Delphinus
12-28-2011, 03:42 PM
There's an easy way of proving that 0.999... = 1.

1/3 = 0.333...
0.333... * 3 = 0.999...
1/3 * 3 = 1
Therefore 0.999... = 1

EDIT: It's not mathematically rigorous as it doesn't prove it from first principles but it's good enough. Anyone with a degree in symbolic logic or maths to give a better proof?

Hayashida
12-29-2011, 01:59 PM
James if you like this sort of thing you would love a show called QI.

CypressDahlia
12-29-2011, 02:11 PM
Delphinus that doesn't prove it considering .333 is merely a numerical representation of the fact that an exact third cannot exist.

Hayashida
12-29-2011, 02:40 PM
what 1/3 of something can totally exist

CypressDahlia
12-29-2011, 02:46 PM
a third of something can exist. 1/3 cannot. Get it. 1 divided by 3. 1 over 3. 1 dividido por 3.

Bacon_Barbarian
12-29-2011, 02:56 PM
There's an easy way of proving that 0.999... = 1.

1/3 = 0.333...
0.333... * 3 = 0.999...
1/3 * 3 = 1
Therefore 0.999... = 1

EDIT: It's not mathematically rigorous as it doesn't prove it from first principles but it's good enough. Anyone with a degree in symbolic logic or maths to give a better proof?

I dunno' should I get my dad to look at this?

Also, "irregardless" is NOT an actual word. It's a damn stupid Bushism.

Delphinus
12-29-2011, 02:58 PM
A third of something can exist, it just can't be expressed in base 10. You can express it in any base number system that's a multiple of three.

For example, base 3 (0, 1, 2 - each place represents another power of three, so 111 in base three represents:
1(3^0) + 1(3^1) + 1(3^2) =
1(1) + 1(3) + 1(9) =
1 + 3 + 9 = 13

You can represent 1/3 exactly in base three, really easily. It's simply 0.1. This is because a decimal point symbolises the point where numbers go into negative powers, making 0.1 in base 3 equivalent to:

0(3^0) + 1(3^-1) =
0(3) + 1(1/3) =
0 + 1/3 =
1/3

I tried to simplify that for people who haven't done mathematics classes, but I dunno how successful I've been. Basically, a third of something can exist in exactly the same way as a tenth of something can; it's just that the number system we use (denary, or base 10) can't express it. If you ask me, duodecimal (base 12) is a far better system, because it allows you to express numbers divided by 1,2,3,4,6, and any multiples of those numbers. The only one you can't express correctly with it is a multiple of 5.

You could solve that problem by switching to base-60, but that might be a bit complex for most people...

CypressDahlia
12-29-2011, 03:06 PM
Then it wouldn't be represented as .3333, therefore .9999 still wouldn't equal 1.

Delphinus
12-29-2011, 04:52 PM
Cyp. You're wrong. You're literally trying to make 1 not equal 1. How a number is represented is unrelated to that number's value.

Stop being so arrogant. Just because you don't understand it, it doesn't make it untrue.


http://www.youtube.com/watch?v=3MLp7YNTznE

GunZet
12-29-2011, 06:07 PM
Bark at the moon.

CypressDahlia
12-29-2011, 06:53 PM
Cyp. You're wrong. You're literally trying to make 1 not equal 1. How a number is represented is unrelated to that number's value.

Your conjecture states that because 1 divided by 3 is commonly understood as .3333, multiplying it again by 3 proves that .999 is equal to 1. I'm saying in .3333 in any form still does not represent an exact third. It's shorthand. Suggesting that a third can be represented in a different base still does not prove your conjecture that .3333 = 1/3rd and therefore .999 = 1/1. .1 in base 3 =/= .3333 in base 10, it equals 1/3rd. The accepted truth is that .9999 = 1 because of the absence of a number small enough to constitute the difference. I'm just saying your particular approach to proving it does not work on that level.

If you just said the lack of real infinitesimals disallows for a difference between .999... and 1, yeah I would have agreed. But even then it's not a proof of equivalence so much as it is an inability to calculate the difference mathematically.

Delphinus
12-29-2011, 07:00 PM
Cype, here's a list of formal proofs by mathematicians.

Please read them. (http://en.wikipedia.org/wiki/0.999...)

CypressDahlia
12-29-2011, 07:07 PM
Yeah I've read all of those. It's pretty much agreed on that .999... is smaller than one by an infinitely tiny amount, which is why it's taken as 1 in all practical application. Lack of real infinitesimals.

Delphinus
12-29-2011, 08:35 PM
Not in the real number system, which everyone but mathematicians uses. It's a confusion of symbols. :D

CypressDahlia
12-29-2011, 09:38 PM
Then I guess we agree.

GunZet
12-29-2011, 09:41 PM
You only agree 1/3 of the way.

CypressDahlia
12-29-2011, 09:55 PM
I'd wager it's more like .3333% of the way.

Fenn
12-29-2011, 10:59 PM
Delphinus that doesn't prove it considering .333 is merely a numerical representation of the fact that an exact third cannot exist.

But it can in real life? This is where math really trips me up...

Delphinus
12-30-2011, 09:37 AM
Yes.

Let's give one pie the value of 3. Cut it into 3 slices, and each slice is 1.

Give the same pie the value of 1 and each slice is 1/3 or 0.333...; whichever metric you choose is arbitrary. s = p/3 where s = slice and p = pie, that is all.

If you want to be pernickety, you're just cutting the pie into 3 sections containing an equal amount of molecules, meaning p is going to be more like 100,000,000 than 1 anyway.

Not that you'll ever get an exact third when you cut a pie into 3 slices anyway, but never mind that.

Harvester_Of_Sorrow
12-30-2011, 11:10 AM
Oh, I like this sorta thing.

Nothing rhymes with the words 'Orange' or 'Silver' or 'Purple'

Blorenge, a small town in Wales, and Lozenge, as in those things you suck when you have a sore throat. And the Chilver (sp?) which is an ancient Hindu religious text. Herple, meaning to limp or hobble and Curple which is a strap used by horse riders on horses. I hate it when people try to be interesting by saying certain words have no rhymes.

The Beatles spell the letters H.E.L.P. on the Album cover of 'HELP' in semaphore.

Actually it spells N.U.J.V. Many silly conspiracy theories have come about from this, buts its simply because the guy doing the photo shoot thought it looked better.

Don't go swimming for 30 minutes after you have eaten.

You can, nothing will happen to you at all.

Cracking your knuckles will give you arthritis

No it won't.

The British use 'the V sign' as an insult because in medivial times when they were fighting the French, when a Welsh longbowman was captured by the enemy they would cut off the index and middle finger on his right hand, so the British used to show them their index and middle fingers before battles as a jeer to the French.

There is absoulty no evidence for this. Incidently every single Dutch person I have ever met while abroad has told me this story. Could the Dutch please stop doing that? Thank you.

They all laughed at Christopher Columbus when he thought the world was round.

Actually, he thought the world was pair shaped.

In certain towns in England, you can still legally shoot a welshman with a crossbow on a certain day of the week.

Ofcourse you can't, darling, that would be murder, wouldn't it? That one really annoys me.

The daddy long legs has the strongest venom known to man, but, don't worry, its doesnt have any teeth.

Hmm. I think this one goes without saying.

If you see a woman with an adams apple, shes a transsexual

Woman do have adams apples, they're just not as big as mens.

There are 50 states in the USA.

46, actually. The states of Kentucky, Virginia, Pennsylvania and Massachussetts are commonwealths. I only add this one because its starnge how many Americans are unaware of this.

Roman Emperors used to put their thumbs down to signal the death of a gladiator in the Collosseum.

They used to put their thumbs up, in fact. If they wanted to save them they would put their thumbs out to the side and then put it back inside their fist.

The dust in your house is mostly made up of human skin.

I think this one was made up by the people who make and market cleaning products. A pathetically small amount of human skin is in dust. What is actually in it depends on where you live, your lifestyle, weather you own a pet etc, but it is not true that most of it is peoples discarded skin.

Thats all I got right now...

Delphinus
12-30-2011, 12:26 PM
In certain towns in England, you can still legally shoot a welshman with a crossbow on a certain day of the week.

Ofcourse you can't, darling, that would be murder, wouldn't it? That one really annoys me.

I looked this up at one point. Turns out that it is legal, but only under the old medieval common law system. The more recent statutory laws against all murder override the common law; it's just that the medieval law was never formally withdrawn, presumably because it was unnecessary to do so.

digitek
12-30-2011, 02:55 PM
Same applies with the law stating that (until 1976) every taxi had to have a bale of hay in the back to feed the horses, and apparently they are all illegal because they don't do this. Well, the other day I saw a taxi with at least 4 crates of beer in the boot... so I don't know what kind of horses he's feeding.

Fenn
12-30-2011, 03:47 PM
Delph's second explanation makes sense. Sometimes i forget math is limited by the way we represent it. So base-10 simply cannot express 1/3 properly.

Bacon_Barbarian
12-30-2011, 04:16 PM
There are 50 states in the USA.

46, actually. The states of Kentucky, Virginia, Pennsylvania and Massachussetts are commonwealths. I only add this one because its starnge how many Americans are unaware of this.

No. They are States. They're just constituted as commonwealths. Different.

jubeh
12-30-2011, 04:39 PM
Its just a paper thing. If they weren't states they wouldn't get senators or people in the house.

Harvester_Of_Sorrow
12-30-2011, 04:46 PM
No. They are States. They're just constituted as commonwealths. Different.

So they're called commonwealths but their actually States? Interesting.

Bacon_Barbarian
12-30-2011, 04:50 PM
Yep. Sort of silly. And what Jubeh said.

butternut
12-31-2011, 03:17 AM
And the Chilver (sp?) which is an ancient Hindu religious text.

Chilver is not a text. It is a female lamb. I am a Hindu and I never heard of it, so googled it up.

Hayashida
12-31-2011, 03:34 AM
So they're called commonwealths but their actually States? Interesting.

Do you watch QI chris

Harvester_Of_Sorrow
01-01-2012, 02:35 PM
Do you watch QI chris

Hell yeah, its a great show. I just wish Jo Brand wasn't on it so much. That woman is about as funny as typhoid.

And I appreciate your correction, saphira, it appears I was fed misinformation on that one. Hinduism is a religion I would like to learn alot more about, my current understanding is fairly basic.

Hayashida
01-01-2012, 06:33 PM
Jo Brand is better than Sue Perkins anyway but they should put Bill Bailey on more than Jo.

butternut
01-02-2012, 01:43 AM
And I appreciate your correction, saphira, it appears I was fed misinformation on that one. Hinduism is a religion I would like to learn alot more about, my current understanding is fairly basic.

Thank you! I'd love to help you, but I myself don't know a lot other than the stuff my parents and grandparents told me (which is mainly related to all the festivals and traditions that appear in everyday life). There's tons of texts and stories and some of the mythology is p.confusing (all the names and roles played). Now, I kinda have my own understanding of it (based on whatever I know). Anyway, ask me what you want to know, i'll tell ya, or I'll refer you if I don't know. =)

Oh! and some aspects are very related to ancient history as well. Right now, I want to check if I'm right about something, so I want to learn more about Harappan culture (or Indus Valley Civilization).

CypressDahlia
01-02-2012, 02:19 AM
some people think Chilver is an ancient Hindu text but it's actually a female lamb

Harvester_Of_Sorrow
01-02-2012, 08:49 AM
It is also quite possible that the spelling is different.