# Common Misconceptions Many Reasonably Intelligent People Have and Your Corrections **URL:** \ **Category:** In My Humble Opinion\ **Created:** [May 9, 2011, 2:24am UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226 "2011-05-09T02:24:01Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![suranyi](https://avatars.discourse-cdn.com/v4/letter/s/e36b37/32.png) [@suranyi](https://boards.straightdope.com/u/suranyi)\ **Post date:** [May 9, 2011, 3:42pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/41 "2011-05-09T15:42:50Z")
> [@Moonlitherial](#): > > It’s now law in Canada that they need to print rather prominently on the bill exactly how long it would take to pay off your credit card assuming you always pay only the minimum payment and never add additional charges to the card. > > It only became law late last year so I am still amused by reading the boxes. They range from 10-30 years. That seems to be the case here in the US as well. For the last several months all of my credit card statements have included this information. ---
**Author:** ![LionelHutz405](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lionelhutz405/32/536_2.png) [@LionelHutz405](https://boards.straightdope.com/u/LionelHutz405)\ **Post date:** [May 9, 2011, 3:49pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/42 "2011-05-09T15:49:39Z")
Real estate is a good investment because it always go up in value. ---
**Author:** ![Snickers](https://avatars.discourse-cdn.com/v4/letter/s/5daacb/32.png) [@Snickers](https://boards.straightdope.com/u/Snickers)\ **Post date:** [May 9, 2011, 3:51pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/43 "2011-05-09T15:51:17Z")
> [@NinetyWt](#): > > 1. “If we get a 100-year flood this year, it will be 99 more years until the next one.” FALSE. A “100-year flood” describes the _magnitude_ of the flooding. It is expected to occur _at least once_ within a 100-year period. In actuality it can occur more frequently than that. Especially if you live in North Dakota. I swear, they’ve had 100-year floods the past 7 out of 9 years. North Dakota floods, the west burns - it’s a truism. ---
**Author:** ![Hypno-Toad](https://avatars.discourse-cdn.com/v4/letter/h/b2d939/32.png) [@Hypno-Toad](https://boards.straightdope.com/u/Hypno-Toad)\ **Post date:** [May 9, 2011, 4:00pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/44 "2011-05-09T16:00:48Z")
> [@voltaire](#): > > And, as Shagnasty touched on, just because you can claim a write-off/deduction for something you paid $1000 for, doesn’t mean you pay $1000 less in taxes. It means you pay taxes on $1000 less income. (And that’s ONLY IF, as I mentioned above, ALL your other write-offs/deductions have already exceeded the standard deduction.) So assuming an average tax-rate of 15%, that one $1000 “write-off” may save you anywhere from $0 to $150 - hardly the “it’s on the government’s tab, and practically free” it’s often portrayed to be when people cite a “write-off” as justification for a purchase. I remember being very dissillusioned by this on the very first time I did my taxes. I thought I was going to be getting thousands back because I had put a few grand into my IRA and it was “tax deductable.” As I was actually filling out the form and saw the truth, It was most dissappointing. ---
**Author:** ![Martin\_Hyde](https://avatars.discourse-cdn.com/v4/letter/m/47e85d/32.png) [@Martin\_Hyde](https://boards.straightdope.com/u/Martin_Hyde)\ **Post date:** [May 9, 2011, 4:05pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/45 "2011-05-09T16:05:02Z")
> [@MsWhatsit](#): > > A lot of people seem to think that the indexes in the backs of books are somehow automatically generated via computer. > > Actually they are composed by professional indexers (like me!), most of whom do this on a freelance basis. > > Edit: This may be esoteric enough to be DQ’ed by the OP’s rules, but I’ve run into enough people who think this that I thought I’d mention it. I wanted to say that despite reading tons of history books in my life with heavy indexes, even going back to the 70s, I never once thought about how the index was created. I didn’t think it was created by computer, but until this moment I never imagined a human being actually going through and doing it, I find it strangely interesting that there is a profession for this :). ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [May 9, 2011, 4:15pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/46 "2011-05-09T16:15:10Z")
> [@Meme\_Chose](#): > > No, you did NOT catch a cold standing in the rain last night. You came into contact with a virus several days ago. On that same vein (heh)- you did not get the flu from your flu shot. It’s flu season, you were exposed before you got the shot, or you are having mild side effects of the shot- but not the flu itself. ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [May 9, 2011, 4:18pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/47 "2011-05-09T16:18:12Z")
> [@WotNot](#): > > Hadrian’s Wall does not mark the border between England and Scotland, nor has it ever done so. Heh. When Hadrian’s Wall was built, the English were still living in Germany and the Scots were still living in Ireland. ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [May 9, 2011, 4:24pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/48 "2011-05-09T16:24:46Z")
> [@Biggirl](#): > > We did not evolve from monkeys. Both believers and deniers of evolution think this. This is wrong. It is especially wrong when someone tries to debunk evolution by saying, “If we evolved from monkeys, why are there still monkeys?” That statement is wrong for more than one reason. > > Monkeys and humans evolved from a common ancestor. And just because a species evolves from a common ancestor does not mean that this ancestor ups and dissolves once another species evolves away from it. OK, I’m going to comment on this one too. Humans are mammals, right? It’s not exactly wrong to say “we evolved from mammals”, in the sense that our ancestors were mammals. But it is misleading since it implies that we’re no longer mammals. So it turns out that humans ARE monkeys. Primates are a particular kind of mammals, monkeys are a particular kind of primate, apes are a particular kind of monkey, and humans are a particular kind of ape. So humans evolved from monkeys in the same way that baboons and gorillas and macaques evolved from earlier monkeys. In the same way it’s sort-of correct to say that birds evolved from dinosaurs, but it’s more correct to say that birds ARE dinosaurs. ---
**Author:** ![monstro](https://avatars.discourse-cdn.com/v4/letter/m/ba9def/32.png) [@monstro](https://boards.straightdope.com/u/monstro)\ **Post date:** [May 9, 2011, 4:33pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/49 "2011-05-09T16:33:23Z")
An outlier is a statistical term that is determined using statistical tests. It is incorrect to simply look at a spread of data points and arbitrarily determine that this or that one are outliers. Statiscians have actually devised methods for doing this. Schizophrenia does not involve having “multiple personalities”. So saying “The weather has been pretty schizophrenic lately” is a misproper use of the term (even though it’s so common that it’s kind of a jerkish to correct people about it). Pollution does not always mean toxic substances. Dirt (sediments) is a pollutant. And nutrients aren’t good in your local waterways. Yes, fish need nutrients just like the rest of us, but they don’t need help from humans to get them. Mitigating excess nitrogen and phosphorus in streams, rivers, and lakes is actually more problematic and expensive than fixing “toxic pollutant” problems. Also, while point dischargers (e.g., industrial factories and sewage treatment plants) are not always blameless innocents, they are not the biggest culprit of poor water quality. Agriculture and John and Jane Q. Public are, because in most jurisdictions, there’s no legal enforcement to make sure they comply with the Clean Water Act. ---
**Author:** ![california\_jobcase](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@california\_jobcase](https://boards.straightdope.com/u/california_jobcase)\ **Post date:** [May 9, 2011, 4:38pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/50 "2011-05-09T16:38:23Z")
Butterflies don’t come from cocoons of silk. Moths and a few other insects do. ---
**Author:** ![Peremensoe](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@Peremensoe](https://boards.straightdope.com/u/Peremensoe)\ **Post date:** [May 9, 2011, 4:42pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/51 "2011-05-09T16:42:00Z")
> [@Lemur866](#): > > …So it turns out that humans ARE monkeys… And “fish.” And a bunch of other things. But we did not evolve from the sort of “monkeys” we see in the world today. Those species have had _just as much time to evolve_ since the split as we have. For that matter, yes, we evolved from mammals, we evolved from something that would today likely be called a fish, but not from any of the mammals or any of the fish here _now_. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [May 9, 2011, 4:54pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/52 "2011-05-09T16:54:39Z")
> [@spark240](#): > > You’d think the spinning would tend to throw us off! It does. Disregarding local variations in the actual attractive force of gravity, a person standing on the equator (and therefore orbiting the center of the earth at 1041 MPH) would perceive a gravity to be 99.6% of what he felt standing at either pole. A person flying east along the equator on a 747 (ground speed 600 MPH) would experience 99.1% of what he felt at either pole. The pilot of an [SR-71](http://en.wikipedia.org/wiki/Sr-71) flying east along the equator (ground speed 2100 MPH) would experience 96.9% of what he felt at either pole; something dropped in the cockpit would accelerate toward the pilot’s feet only 96.9% as rapidly as would happen if the plane were parked at the north pole. ---
**Author:** ![fachverwirrt](https://avatars.discourse-cdn.com/v4/letter/f/94ad74/32.png) [@fachverwirrt](https://boards.straightdope.com/u/fachverwirrt)\ **Post date:** [May 9, 2011, 4:56pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/53 "2011-05-09T16:56:17Z")
> [@Lemur866](#): > > OK, I’m going to comment on this one too. > > Humans are mammals, right? It’s not exactly wrong to say “we evolved from mammals”, in the sense that our ancestors were mammals. But it is misleading since it implies that we’re no longer mammals. > > So it turns out that humans ARE monkeys. Primates are a particular kind of mammals, monkeys are a particular kind of primate, apes are a particular kind of monkey, and humans are a particular kind of ape. > > So humans evolved from monkeys in the same way that baboons and gorillas and macaques evolved from earlier monkeys. In the same way it’s sort-of correct to say that birds evolved from dinosaurs, but it’s more correct to say that birds ARE dinosaurs. My understanding is that apes and monkeys are two distinct types of primates. That is, apes are not a subset of monkeys, but an entirely separate branch. The primates are divided into the prosimians and the simians, and simians are divided into monkeys and apes. Humans, being apes, are therefore not, in fact, monkeys. At least, as far as I know. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [May 9, 2011, 5:01pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/54 "2011-05-09T17:01:34Z")
> [@fachverwirrt](#): > > My understanding is that apes and monkeys are two distinct types of primates. That is, apes are not a subset of monkeys, but an entirely separate branch. The primates are divided into the prosimians and the simians, and simians are divided into monkeys and apes. Humans, being apes, are therefore not, in fact, monkeys. At least, as far as I know. See here: [So scientifically speaking, apes are a kind of monkey.](http://boards.straightdope.com/sdmb/showpost.php?p=13723230&postcount=6). ---
**Author:** ![california\_jobcase](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@california\_jobcase](https://boards.straightdope.com/u/california_jobcase)\ **Post date:** [May 9, 2011, 5:01pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/55 "2011-05-09T17:01:41Z")
Oil and water don’t mix because oil is less dense than water. (really, they don’t mix because oil is non-polar and water is polar) ---
**Author:** ![fachverwirrt](https://avatars.discourse-cdn.com/v4/letter/f/94ad74/32.png) [@fachverwirrt](https://boards.straightdope.com/u/fachverwirrt)\ **Post date:** [May 9, 2011, 5:12pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/56 "2011-05-09T17:12:10Z")
> [@Sailboat](#): > > See here: [So scientifically speaking, apes are a kind of monkey.](http://boards.straightdope.com/sdmb/showpost.php?p=13723230&postcount=6). Fair enough. That seems to speak more to the idea that monkey is just an inaccurate term than anything else (or at least that new and old world monkeys should be referred to separately). Or, as wikipedia says, “monkey” is not a good taxon. At any rate, I can say with confidence that I am not a Monkee. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [May 9, 2011, 5:13pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/57 "2011-05-09T17:13:11Z")
> [@california\_jobcase](#): > > Oil and water don’t mix because oil is less dense than water. > > (really, they don’t mix because oil is non-polar and water is polar) Likewise, the Pennsylvania Fish and Boat Commission has PSAs that proclaim, “Water and Alcohol Don’t Mix”. I always scowl and explain to whomever I’m with that they most certainly do. ---
**Author:** ![Hypno-Toad](https://avatars.discourse-cdn.com/v4/letter/h/b2d939/32.png) [@Hypno-Toad](https://boards.straightdope.com/u/Hypno-Toad)\ **Post date:** [May 9, 2011, 5:20pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/58 "2011-05-09T17:20:22Z")
> [@fachverwirrt](#): > > At any rate, I can say with confidence that I am not a Monkee. When you’re walking down the street, do you get the funniest looks from everyone you meet? ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [May 9, 2011, 5:22pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/59 "2011-05-09T17:22:07Z")
Colgan Air Flight 3407 did not crash because of iced wings. Any ice build up on the wings wasn’t sufficient enough to particularly affect the flight, and the deicing system was turned on. Alongside this fact, the plane did not enter an icing-induced tail stall to trigger the accident sequence; this was mentioned early in the investigation as something the _Dash-6_ is susceptible to, but the design of the Dash-8 (especially the Q400) is such that if your tail has stalled, you are well into a wing stall already! My fluid and aerodynamics profs at school continually point to this crash as an example of things that can affect/reduce lift, but they are simply wrong about the facts of the situation. The TV episode of _Mayday_ which covers this accident also points to icing as part of the cause. This episode was produced before the accident report even came out, and they are simply wrong. ---
**Author:** ![phreesh](https://avatars.discourse-cdn.com/v4/letter/p/9fc29f/32.png) [@phreesh](https://boards.straightdope.com/u/phreesh)\ **Post date:** [May 9, 2011, 5:34pm UTC](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226/60 "2011-05-09T17:34:35Z")
> [@california\_jobcase](#): > > Butterflies don’t come from cocoons of silk. Moths and a few other insects do. I am, apparently, suffering a misconception about this. Are you saying that butterflies don’t come from cocoons or that they don’t come from _silk_ cocoons? Because I thought they came from cocoons (maybe created from leaves or other materials). [Previous page](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226.md?page=2) [Next page](https://boards.straightdope.com/t/common-misconceptions-many-reasonably-intelligent-people-have-and-your-corrections/581226.md?page=4)