# What is the smallest human that can exist and still obey the laws of physics? **URL:** \ **Category:** Factual Questions\ **Created:** [January 23, 2010, 4:56am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079 "2010-01-23T04:56:08Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Cornelius\_Tuggerson](https://avatars.discourse-cdn.com/v4/letter/c/13edae/32.png) [@Cornelius\_Tuggerson](https://boards.straightdope.com/u/Cornelius_Tuggerson)\ **Post date:** [January 23, 2010, 4:56am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/1 "2010-01-23T04:56:08Z")
There is a ton of movies out there depicting giant spiders and such, but we all know they could not possibly be real(on earth) due to the ole m1_m2/2_G which would(with m2 equaling the mass of earth) crush their bones and turn them into an amusing, albeit physically impossible source of nutrition. So say I had a shrink ray that could shrink humans, whats the tiniest viable human I could achieve based on earth’s gravity, bloods surface tension and so on? I ask because I am worried, what if these movies weren’t about giant spiders, what if they were about tiny humans! Need answer fast! ---
**Author:** ![Ruminator](https://avatars.discourse-cdn.com/v4/letter/r/b9bd4f/32.png) [@Ruminator](https://boards.straightdope.com/u/Ruminator)\ **Post date:** [January 23, 2010, 4:59am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/2 "2010-01-23T04:59:12Z")
Do you need the whole body or is a brain in a vat enough to be considered “human”? (Btw, I wouldn’t know the answer either way.) ---
**Author:** ![Cornelius\_Tuggerson](https://avatars.discourse-cdn.com/v4/letter/c/13edae/32.png) [@Cornelius\_Tuggerson](https://boards.straightdope.com/u/Cornelius_Tuggerson)\ **Post date:** [January 23, 2010, 5:08am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/3 "2010-01-23T05:08:11Z")
I mean the entire human body, with the right vat pressure you could get a human brain to survive under any gravity, provided the relative pressure of the blood being pumped in stayed close to what it is in nature. ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [January 23, 2010, 6:37am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/4 "2010-01-23T06:37:37Z")
Okay. 1) That formula is wrong. [F[sub]g[/sub] = Gm[sub]1[/sub]m[sub]2[/sub]/d[sup]2[/sup] .](http://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation) 1. How are we shrinking these humans? Are we just compressing them, making them very dense? Or are we selectively removing a proportion of their atoms? Because either way there are going to be grave consequences, and I don’t see any other way of doing it. You’re going to screw up the cellular structure and biochemistry before your human gets much smaller than a midget. ---
**Author:** ![Stealth\_Potato](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@Stealth\_Potato](https://boards.straightdope.com/u/Stealth_Potato)\ **Post date:** [January 23, 2010, 7:31am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/5 "2010-01-23T07:31:26Z")
> [@Cornelius\_Tuggerson](#): > > …an amusing, albeit physically impossible source of nutrition. Um. If _you_ want to eat freshly crushed giant spider, please, by all means, knock yourself out. Me? I’m going to be over here, horking into these bushes. :o ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [January 23, 2010, 2:01pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/6 "2010-01-23T14:01:12Z")
If you make the brain much smaller than it is now, it wouldn’t be a human. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [January 23, 2010, 2:05pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/7 "2010-01-23T14:05:04Z")
You can have a physically functional “monkey” type primate as small as a [Pygmy Marmoset](http://en.wikipedia.org/wiki/Pygmy_Marmoset). The main issue is brain size and I don’t know how small that can get before you start to lose normative human intellectual capacity. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [January 23, 2010, 2:15pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/8 "2010-01-23T14:15:14Z")
> [@Cornelius\_Tuggerson](#): > > I ask because I am worried, what if these movies weren’t about giant spiders, what if they were about tiny humans! Check out \*The Incredible Shrinking Man \* (1957) in which the hero fights a gigantic (i.e. normal sized) [spider](http://www.imdb.com/media/rm2488178688/tt0050539). Classic movie, well worth seeing. ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [January 23, 2010, 2:19pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/9 "2010-01-23T14:19:42Z")
Isaac Asimov wrote a column on this topic back in 1969, when the tv show “Land of the Giants” was on. The column was titled “The Incredible Shrinking People” and it was re-published in book form in 1969 in _The Solar System and Back_. His general thesis was that miniaturization was impossible, because of the minimal number of neurons needed to keep the brain working - that number would collide with the size of atoms. (At least, that’s my non-scientific recollection - it’s been a while since I read it.) ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [January 23, 2010, 2:25pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/10 "2010-01-23T14:25:03Z")
> [@Cornelius\_Tuggerson](#): > > whats the tiniest viable human I could achieve … Babies have survived who were born at 25 weeks, weighing less than a pound. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [January 23, 2010, 2:25pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/11 "2010-01-23T14:25:37Z")
There are arguments back and forth that even the Hobbits (\*Homo floresiensis) \*had too small of a brain capacity for tool use. These near men were only about 3’ 6" in height from the few samples so far found and reported on. Khagendra Thapa Magar of Nepal is only 22" tall and 12 lbs at age 18. He appears to be the shortest man on record. He does suffer from learning disabilities though but is apparently learning to read. There have been a few other adults recorded for similar heights. Jyoti Amge of India is only 23" tall and has normal mental capabilities. She is 16. So 2’ might be the reasonable limit, especially if you can shrink the body more than the head. All of these men seem to be what use to be referred to as Dwarves. Little People where the head is out of proportion to the body. Hopefully that helps as a bit of a baseline at least. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [January 23, 2010, 2:44pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/12 "2010-01-23T14:44:07Z")
> [@Northern\_Piper](#): > > Isaac Asimov wrote a column on this topic back in 1969, when the tv show “Land of the Giants” was on. The column was titled “The Incredible Shrinking People” and it was re-published in book form in 1969 in _The Solar System and Back_. > > His general thesis was that miniaturization was impossible, because of the minimal number of neurons needed to keep the brain working - that number would collide with the size of atoms. (At least, that’s my non-scientific recollection - it’s been a while since I read it.) But he made a good job of justifying it in his novelisation of _Fantastic Voyage_. In his re-working of the script, every atom got smaller and less massive. Therefore the miniatured humans retained all their neurons. ---
**Author:** ![gonzomax](https://avatars.discourse-cdn.com/v4/letter/g/e8c25b/32.png) [@gonzomax](https://boards.straightdope.com/u/gonzomax)\ **Post date:** [January 23, 2010, 4:56pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/13 "2010-01-23T16:56:56Z")
[World's Tallest Man, Sultan Kosen, Meets One Of The World's Shortest, He Pingping (PICTURES) | HuffPost The World Post](http://www.huffingtonpost.com/2010/01/22/worlds-tallest-man-sultan_n_433940.html) Here is the long and short of it nowadays. 2 ft 5 is pretty small. ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [January 23, 2010, 5:17pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/14 "2010-01-23T17:17:20Z")
> [@Chief\_Pedant](#): > > If you make the brain much smaller than it is now, it wouldn’t be a human. This little person is [sad](http://sinekpartners.typepad.com/photos/uncategorized/2008/08/04/baby.jpg) that you think he’s not human. This little person is [upset](http://cphclubpenguinhurricanes.files.wordpress.com/2009/04/baby.jpg). ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [January 23, 2010, 11:15pm UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/15 "2010-01-23T23:15:05Z")
> [@Tom\_Tildrum](#): > > This little person is [sad](http://sinekpartners.typepad.com/photos/uncategorized/2008/08/04/baby.jpg) that you think he’s not human. This little person is [upset](http://cphclubpenguinhurricanes.files.wordpress.com/2009/04/baby.jpg). What are you talking about? Babies’ brains are not smaller than human brains are now, they are exactly the same size as (their own) human brains are now. Incidentally, spiders don’t have bones. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [January 24, 2010, 12:02am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/16 "2010-01-24T00:02:45Z")
> [@Tom\_Tildrum](#): > > This little person is [sad](http://sinekpartners.typepad.com/photos/uncategorized/2008/08/04/baby.jpg) that you think he’s not human. This little person is [upset](http://cphclubpenguinhurricanes.files.wordpress.com/2009/04/baby.jpg). By your reasoning, [this](http://www.abortion.org.au/brainwaves.jpg) little guy is suicidal. Lemme make it easier for you: If you make the fully developed adult brain much smaller than it is now, it wouldn’t be a human. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [January 24, 2010, 1:29am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/17 "2010-01-24T01:29:53Z")
> [@Chief\_Pedant](#): > > \Lemme make it easier for you: If you make the fully developed adult brain much smaller than it is now, it wouldn’t be a human. Define “smaller than it is now”. The adult human brain comes in a range of sizes. Primordial dwarfs have much smaller brains, too, but they certainly are human. So, I would say that we know we can make it as small as the smallest person with that condition. It doesn’t say how small her brain was, but [Lucia Zarate](http://en.wikipedia.org/wiki/Lucia_Zarate) weighed less than 5 pounds at age 17. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [January 24, 2010, 4:12am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/18 "2010-01-24T04:12:42Z")
> [@John\_Mace](#): > > Define “smaller than it is now”. The adult human brain comes in a range of sizes. > > Primordial dwarfs have much smaller brains, too, but they certainly are human. So, I would say that we know we can make it as small as the smallest person with that condition. It doesn’t say how small her brain was, but [Lucia Zarate](http://en.wikipedia.org/wiki/Lucia_Zarate) weighed less than 5 pounds at age 17. I’d say much smaller than my buddy [Aditya Dev, with me on the left](http://images.google.com/imgres?imgurl=http://ramkeshar.files.wordpress.com/2009/06/aditya-dev-worlds-smallest-body-builder-near-dumbb1.jpg&imgrefurl=http://ramkeshar.wordpress.com/2009/06/06/aditya-dev-fotos/&usg=__P-qOm0zHI3O65TURDvVEuuMXdhI=&h=691&w=468&sz=67&hl=en&start=1&sig2=bUr-8azNGvOAgbnTojsfgQ&um=1&tbnid=UDEARvYE8UhWOM:&tbnh=139&tbnw=94&prev=/images%3Fq%3DAditya%2BDev%26hl%3Den%26rlz%3D1C1GGLS_enUS352US352%26sa%3DN%26um%3D1&ei=esdbS8GnGJKsM6qltYkP) and the loss of cranial capacity would diminish the humanness of what’s left. My point is there is a lower limit. You can’t take us down to beetle size, like in the movies. Rumor to the contrary, all that white and grey matter actually does something. Most primordial dwarf types, and obviously all the ones with microcephaly, are mentally retarded. Russel-Silvers may not be mentally handicapped, but they have larger cranial capacities than other types, on average. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [January 24, 2010, 4:20am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/19 "2010-01-24T04:20:33Z")
Missed edit: These mentally challenged folks are still obviously fully human, but if all humans had very small brains, humanness would be an entirely different thing… ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [January 24, 2010, 5:15am UTC](https://boards.straightdope.com/t/what-is-the-smallest-human-that-can-exist-and-still-obey-the-laws-of-physics/526079/20 "2010-01-24T05:15:30Z")
> [@Peter\_Morris](#): > > But he made a good job of justifying it in his novelisation of _Fantastic Voyage_. In his re-working of the script, every atom got smaller and less massive. Therefore the miniatured humans retained all their neurons. True, but that just illustrates the difference between Professor Asimov, Ph.D., and Isaac Asimov, science fiction genius!