# Chen019, you are a liar. **URL:** \ **Category:** The BBQ Pit\ **Created:** [March 9, 2012, 9:43am UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246 "2012-03-09T09:43:10Z")\ **Posts on this page:** 20\ **Page:** 8
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 3:12pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/141 "2012-03-12T15:12:31Z")
you seem to ---
**Author:** ![BrainGlutton](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@BrainGlutton](https://boards.straightdope.com/u/BrainGlutton)\ **Post date:** [March 12, 2012, 3:13pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/142 "2012-03-12T15:13:33Z")
> [@Kimstu](#): > > I repeat: _ **if a racial classification system doesn’t provide reliable information about the actual genetic relationships of members of those races, then what the hell is the point of it?** _ [shrug] If race is a social construct, then any system of racial classification should strive to reflect the socially-defined categories; like the U.S. Census does, and for sociopolitically important reasons. ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 3:25pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/143 "2012-03-12T15:25:29Z")
> [@BrainGlutton](#): > > [shrug] If race is a social construct, then any system of racial classification should strive to reflect the socially-defined categories So 200 years ago, the system classifying ‘negroes’ as subhuman was just fine because it reflected socially defined categories? But, I do agree with part of what you say. Race _is_ a social construct. It has no scientific validity. ---
**Author:** ![gamerunknown](https://avatars.discourse-cdn.com/v4/letter/g/6bbea6/32.png) [@gamerunknown](https://boards.straightdope.com/u/gamerunknown)\ **Post date:** [March 12, 2012, 3:31pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/144 "2012-03-12T15:31:05Z")
> [@](#): > > racial classification should strive to reflect the socially-defined categories Point is, those categories are usually not defined very well and when they are, do not impart any useful information about genotype. ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 12, 2012, 3:31pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/145 "2012-03-12T15:31:48Z")
> [@DocCathode](#): > > you seem to :shrug: You seem to have a different definition of the word “liar” from me. Even putting aside that my statement is correct, if somebody asserts a general conclusion about a controversial issue, it would not occur to me to characterize their statement as a lie – even if I completely disagree with them. And of course my statement was indeed correct, which I can demonstrate pretty easily if you care to lay out the specific criteria by which you (presumably) reject “race” as a set of categories. Put another way: How do I know if a set of categories has “scientific validity”? ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [March 12, 2012, 3:39pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/146 "2012-03-12T15:39:46Z")
> [@BrainGlutton](#): > > [shrug] If race is a social construct, then any system of racial classification should strive to reflect the socially-defined categories; like the U.S. Census does, and for sociopolitically important reasons. Sure. What I meant is that the use of racial categories as any kind of **biological** classification system (which is what the so-called “race realists” keep trying to defend) is absolutely pointless if it doesn’t provide reliable information about genetic relationships. For racial categories used as a **social** classification system, as you note, that requirement is unnecessary and irrelevant. ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 3:41pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/147 "2012-03-12T15:41:54Z")
> [@brazil84](#): > > Even putting aside that my statement is correct, I actually laughed out loud at this. > [@](#): > > if somebody asserts a general conclusion about a controversial issue, it would not occur to me to characterize their statement as a lie – even if I completely disagree with them. It isn’t that you said something I disagree with. It’s that you made a statement you know to be untrue. > [@](#): > > You can make the same objection for many other categories. What other categories exhibit more variation within a category than between two categories. > [@](#): > > And of course my statement was indeed correct, which I can demonstrate pretty easily if you care to lay out the specific criteria by which you (presumably) reject “race” as a set of categories. Put another way: How do I know if a set of categories has “scientific validity”? I think what I just said will do for now. There must be greater variation between two categories than within a category. That isn’t the sole criterion but it will do for a start ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 12, 2012, 3:50pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/148 "2012-03-12T15:50:21Z")
> [@DocCathode](#): > > It isn’t that you said something I disagree with. It’s that you made a statement you know to be untrue. Nonsense, it’s true and I believe it 100%. > [@](#): > > What other categories exhibit more variation within a category than between two categories. :shrug: The difference in height between the tallest man and the shortest man is far greater than the difference in average height between men and women. Or are you measuring variation in some other way? If so, how? ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 3:55pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/149 "2012-03-12T15:55:53Z")
> [@brazil84](#): > > :shrug: The difference in height between the tallest man and the shortest man is far greater than the difference in average height between men and women. > > Or are you measuring variation in some other way? If so, how? But height is not a defining characteristic of sex. I gave those in the GD thread that started this- Chromosomes Genitalia and reproductive organs brain (specifically the bed of the hypothalmus) ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 12, 2012, 4:27pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/150 "2012-03-12T16:27:28Z")
> [@DocCathode](#): > > But height is not a defining characteristic of sex. :shrug: the difference in BMI between the most and least obese people (among the obese) is surely far more than the difference in average BMIs between obese people and non-obese people. ---
**Author:** ![tomndebb](https://avatars.discourse-cdn.com/v4/letter/t/b9e5f3/32.png) [@tomndebb](https://boards.straightdope.com/u/tomndebb)\ **Post date:** [March 12, 2012, 4:54pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/151 "2012-03-12T16:54:57Z")
> [@magellan01](#): > > What term would you prefer for African Blacks? Negroids? Africanus? Use whatever you’d like. Same for Asians/Orientals…any term you’d like. Caucasians/Whites, whatever you’d like. I’m really not interested in the game of you insisting that any term be as infallible as the definition of isosceles triangle. Why would anyone want a “term” for separate, discrete groups as though they were part of one group? In Africa, among people who would be called “black” if they lived in the U.S., are several separate groups. Why would we want a term, (in biology), to lump them together whjen they are not “together” in any biological sense. The same holds true for “Asians/Orientals” or “Caucasians/Whites” with multiple populations who are not closely related. Aside from a general geographic allusion, there does not seem to be any reason to give them a collective term. Particularly when we are discussing biological situations, there is simply no reason to come up with such labels. Giving large, disparate groups single labels is simply a way to cause confusion by implying that there is some commonality that does not actually exist. It is misleading. ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 9:26pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/152 "2012-03-12T21:26:55Z")
From Wikipedia > [@](#): > > These ranges of BMI values are valid only as statistical categories and > [@](#): > > Statistical device > > The BMI is generally used as a means of correlation between groups related by general mass and can serve as a vague means of estimating adiposity. The duality of the BMI is that, whilst easy-to-use as a general calculation, it is limited in how accurate and pertinent the data obtained from it can be. Generally, the index is suitable for recognizing trends within sedentary or overweight individuals because there is a smaller margin for errors.[15] ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 12, 2012, 11:00pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/153 "2012-03-12T23:00:57Z")
> [@DocCathode](#): > > From Wikipedia > > and I’m not sure what your point is here. Is it your position that {obese people} is not a scientifically valid category? And if not, is it because it fails your variation test, or for some other reason? ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 11:16pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/154 "2012-03-12T23:16:15Z")
> [@brazil84](#): > > I’m not sure what your point is here. Is it your position that {obese people} is not a scientifically valid category? It is my position that the category {obese people} _as defined by BMI_ is not a scientifically valid category. > [@](#): > > And if not, is it because it fails your variation test, or for some other reason? Read the second bit I quoted from Wikipedia. It’s full of weasel words AND also comes right out and says > [@](#): > > it is limited in how accurate and pertinent the data obtained from it can be If the category doesn’t lead to accurate data, what good is it? ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 12, 2012, 11:28pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/155 "2012-03-12T23:28:52Z")
> [@DocCathode](#): > > It is my position that the category {obese people} _as defined by BMI_ is not a scientifically valid category. So can I take it that you categorically reject all scientific studies which are based on this classification? > [@](#): > > Read the second bit I quoted from Wikipedia. I’m not sure I understand your point, but I think I can simplify things with another example. Do you also reject {people with hypertension} as a valid scientific category? ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 11:32pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/156 "2012-03-12T23:32:33Z")
> [@brazil84](#): > > So can I take it that you categorically reject all scientific studies which are based on this classification? More accurate to say that I am somewhat skeptical of them > [@](#): > > I’m not sure I understand your point, but I think I can simplify things with another example. > > Do you also reject {people with hypertension} as a valid scientific category? what gotcha are you trying to spring here I wonder? ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 12, 2012, 11:40pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/157 "2012-03-12T23:40:05Z")
> [@DocCathode](#): > > More accurate to say that I am somewhat skeptical of them Just so we are clear, a scientific study which is based on scientifically invalid categories is not per se invalid . . . it’s simply cause for skepticism of the study . . . is that what you are saying? > [@](#): > > what gotcha are you trying to spring here I wonder? It appears that {people with hypertension} fails your variation test. So by your reasoning, {people with hypertension} is not a valid scientific category. But I would like to know where you stand. ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 12, 2012, 11:51pm UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/158 "2012-03-12T23:51:23Z")
> [@brazil84](#): > > It appears that {people with hypertension} fails your variation test. So by your reasoning, {people with hypertension} is not a valid scientific category. But I would like to know where you stand. I said the variation rule was not the sole criterion. A blood pressure reading in the hypertension range is a reliable indicator of risk for various future problems. Accurate and reliable predictions can be made from the category. ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [March 13, 2012, 12:18am UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/159 "2012-03-13T00:18:01Z")
> [@DocCathode](#): > > I said the variation rule was not the sole criterion. And you also said this: > [@](#): > > There **must** be greater variation between two categories than within a category. (my bolding) So, according to what you said earlier, any categorization which fails your variation test is NOT a valid scientific category. Are you abandoning this position now? > [@](#): > > A blood pressure reading in the hypertension range is a reliable indicator of risk for various future problems. Accurate and reliable predictions can be made from the category. So you agree then that {people with hypertension} IS a valid scientific category? And just so we are clear, you are saying that a scientific study which is based on scientifically invalid categories is not per se invalid . . . it’s simply cause for skepticism of the study . . . right? ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [March 13, 2012, 12:22am UTC](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246/160 "2012-03-13T00:22:46Z")
Now you’re putting words in my mouth, saying I hold a position I never said I held, and JAQing off. I think we’re done here. [Previous page](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246.md?page=7) [Next page](https://boards.straightdope.com/t/chen019-you-are-a-liar/615246.md?page=9)