# How to create a random number generator for 1-6 with just natural supplies in the wilderness? **URL:** \ **Category:** Factual Questions\ **Created:** [January 11, 2018, 5:13pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404 "2018-01-11T17:13:19Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 11, 2018, 9:09pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/41 "2018-01-11T21:09:42Z")
> [@](#): > > Quoth **Chingon** : > > On the count of three, each player puts out a number of fingers (between 1 and 4). If both players pick the same number you try again until they differ. Multiply the two numbers together and map them in the following way: > > 2 -\> 1 > 3 -\> 2 > 4 -\> 3 > 6 -\> 4 > 8 -\> 5 > 12 -\> 6 Even if both players choose their number of fingers randomly, this still isn’t fair. The other numbers all have two ways to come up, but a product of 4 (result of 3 in your mapping) can come up three ways: 1_4, 4_1, or 2\*2. You’re also neglecting 16, but I guess that’s just a re-roll. ---
**Author:** ![Blue\_Blistering\_Barnacle](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/blue_blistering_barnacle/32/3386_2.png) [@Blue\_Blistering\_Barnacle](https://boards.straightdope.com/u/Blue_Blistering_Barnacle)\ **Post date:** [January 11, 2018, 9:14pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/42 "2018-01-11T21:14:40Z")
I like the modulo 6 of sum of six finger signs mentioned upthread. Sounds quick and efficient. Some psch-out potential, though. instead of fancy signs, they could put out 0 (fist) to 5 fingers. You could even do both hands together, and get both dice at once. ---
**Author:** ![snfaulkner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snfaulkner/32/433_2.png) [@snfaulkner](https://boards.straightdope.com/u/snfaulkner)\ **Post date:** [January 11, 2018, 10:35pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/43 "2018-01-11T22:35:14Z")
Step 1) Murder your friend and eat his flesh. Step 2) Whittle dice from his bones. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [January 11, 2018, 10:35pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/44 "2018-01-11T22:35:47Z")
> [@Pasta](#): > > If the goal is to just get a bit from a coin, it needn’t be a fair coin. Flip twice. Reject HH and TT. If TH, bit=0. If HT, bit=1. > > Any bit-by-bit generation, though, strikes me as too inefficient for really playing games unless it was a one-off event. A grid + pebble approach could use grid markings that run from 1 to any small integer (vs. just two types of grid values), and a container full of marked seeds or pebbles drawn with replacement also saves the multi-bit processing. I like this solution the best. I propose a better variant. Throw a coin four times. Six times out of 16 you will get two heads and two tails. Assign each one of the six a number 1 to 6. Ignore the other 10 possibilities. So you get a number 37.5% of the time. I haven’t figured it out, but I guess you will need more throws to get 3 binary digits than you will here to get a number between 1 and 6. ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [January 11, 2018, 11:29pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/45 "2018-01-11T23:29:38Z")
> [@Chronos](#): > > Even if both players choose their number of fingers randomly, this still isn’t fair. The other numbers all have two ways to come up, but a product of 4 (result of 3 in your mapping) can come up three ways: 1_4, 4_1, or 2\*2. > > You’re also neglecting 16, but I guess that’s just a re-roll. You missed the fact that he said re-roll if both players put out the same number of fingers. So it doesn’t suffer from overcounting. But it does still suffer from a player being able to influence the outcome unilaterally. ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [January 12, 2018, 12:50am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/46 "2018-01-12T00:50:20Z")
Pick a decent-sized spruce branch, and count the needles, modulo 6. Hey, you was looking for a way to pass time! ---
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [January 12, 2018, 12:56am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/47 "2018-01-12T00:56:37Z")
Find six pebbles of similar, but clearly different sizes (representing 1-6). Player one buries them in the sand in a random no pattern area at the same depth about the size of a dinner plate with out player two looking and smooth’s out the top of the sand. Player two would then poke a finger in the sand and with a swirling motion pulls out the first rock that gets exposed. You may need a flat surface to place the rocks under the sand so that they are all the same depth. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [January 12, 2018, 3:06am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/48 "2018-01-12T03:06:01Z")
> [@snfaulkner](#): > > Step 1) Murder your friend and eat his flesh. > Step 2) Whittle dice from his bones. Annnd… scene. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 12, 2018, 3:28am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/49 "2018-01-12T03:28:40Z")
The first rock to get exposed would be more likely to be the largest one. ---
**Author:** ![glowacks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/glowacks/32/5548_2.png) [@glowacks](https://boards.straightdope.com/u/glowacks)\ **Post date:** [January 12, 2018, 4:58am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/50 "2018-01-12T04:58:02Z")
Have 6 distinct objects, and 6 numbered areas of sand. Have one person put one of the objects on each of the areas of sand while the other is looking away, then the former person moves into the sight of the latter but the latter remains without sight of the objects and names an object. The person positioning the objects would be unable to influence which object was on which area while in view of the person making the selection, and so could not change things once he knows what the other person is going to pick. The person without sight of the objects that picks one has no knowledge of where each of the objects are. Thus neither player can meaningfully physically influence the outcome, but might through psychologically outwitting the other person. That might be seen as a virtue to this system, not a drawback, adding to the game that one is playing. So not random, but just as good. ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [January 12, 2018, 6:27am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/51 "2018-01-12T06:27:16Z")
You guys are going to lots of trouble with leaves and rocks and stuff when we already have fingers. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [January 12, 2018, 11:12am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/52 "2018-01-12T11:12:25Z")
I think the OP is flawed - I don’t think it’s that hard to make dice which are fair enough to play backgammon with. They don’t have to be cubes, barrel dice or [top dice](http://thewoodenwagon.com/Merchant2/graphics/00000001/GM223-2.jpg) are probably easier to make with primitive supplies, as you can turn them - make a [bow lathe](http://www.turningtools.co.uk/history2/illustrations/bowlathe2.html). ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [January 12, 2018, 11:43am UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/53 "2018-01-12T11:43:36Z")
I plan to sip cocktails and assign two of my monkey butlers to lathing dice. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [January 12, 2018, 12:29pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/54 "2018-01-12T12:29:21Z")
Lay down 6 rocks, representing 1–6 in a pseudo-random order. Your opponent has his back turned. Your opponent picks a number in his head, 1–6, and says it aloud. The number he chooses decides which rock to pick in the order you’ve laid down. So if your rocks are ordered: 5 - 2 - 1 - 6 - 3 - 4 And your opponent says “three”, you’ve rolled a 1. ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [January 12, 2018, 12:36pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/55 "2018-01-12T12:36:49Z")
Growing up back in India in the 70s, there were many traditional board games that were played entirely with natural supplies. This is how we did it : Take [tamarind](https://5.imimg.com/data5/DJ/TJ/MY-1354677/tamarind-seeds-250x250.jpg) seeds or any relatively flat and hard dicotyledon seed. Rub (grind) one side of the seed on a hard surface (concrete floor or flat rock) or split the seed into two. Now you have the equivalent of a small coin with a head and a tail. So for 6, you will use 5 seeds. Each seed (or half of it) will have two sides, and you can assign them 0 and 1. You take the seeds in your hand, close your fist, jiggle them a bit and gently throw them on the ground. You will now get any random number between 0 and 5. You can always designate 0 as 1, and 5 as 6 and this will work just as good as a dice. Also in olden times, Cowry (or Cowrie ) shells were used as dice too. [Cowrie - Wikipedia](https://en.wikipedia.org/wiki/Cowry) See picture at bottom of the linked wiki page. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [January 12, 2018, 12:43pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/56 "2018-01-12T12:43:32Z")
> [@am77494](#): > > So for 6, you will use 5 seeds. Each seed (or half of it) will have two sides, and you can assign them 0 and 1. You take the seeds in your hand, close your fist, jiggle them a bit and gently throw them on the ground. You will now get any random number between 0 and 5. > > You can always designate 0 as 1, and 5 as 6 and this will work just as good as a dice. But adding binary outcomes like this gives a binomial distribution, where the middle values occur much more frequently than the high and low values. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [January 12, 2018, 1:25pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/57 "2018-01-12T13:25:43Z")
Find 6 seashells as nearly identical as possible - pick smallish sea-snail type shells where the opening is too small for a finger Using a piece of grit stuck in the end of a stick, drill a number of dots on the inside of the opening Construct a bag from available materials (weave it from grasses or make a small round basket from palm fronds) - with a large enough opening to admit a human hand Put the shells in the bag and shake it - then reach in and take one out - count the dots and put it back. ---
**Author:** ![SmellMyWort](https://avatars.discourse-cdn.com/v4/letter/s/ea5d25/32.png) [@SmellMyWort](https://boards.straightdope.com/u/SmellMyWort)\ **Post date:** [January 12, 2018, 2:57pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/58 "2018-01-12T14:57:47Z")
> [@filmore](#): > > That would work great, but probably just a few times. The savvy player will start to recognize the sticks and pick them in a specific order. Could the sticks be dumped on the ground and their pattern be used to calculate a number? Or something where a savvy player wouldn’t be able to manipulate the outcome? I think it would be fairly easy to find small sticks/reeds that could be cut/shortened to look nearly identical. They don’t have to be long and if they start to wear replacements are readily available. If one player insists on cheating by trying to study the sticks, then they can always be made to draw with eyes closed or looking away. This really seems to me to strike the best balance between being fair/random enough, easy to find/prep resources, and not impact the speed of the game with needlessly complicated “rolling” schemes. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [January 12, 2018, 3:24pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/59 "2018-01-12T15:24:02Z")
> [@snfaulkner](#): > > Step 1) Murder your friend and eat his flesh. > Step 2) Whittle dice from his bones. Step 3) Roll dem bones ---
**Author:** ![Mr\_Shine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mr_shine/32/464_2.png) [@Mr\_Shine](https://boards.straightdope.com/u/Mr_Shine)\ **Post date:** [January 12, 2018, 3:59pm UTC](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404/60 "2018-01-12T15:59:12Z")
> [@iamthewalrus\_3](#): > > You guys are going to lots of trouble with leaves and rocks and stuff when we already have fingers. The trouble with fingers is that it easily leads to cheating or accusations of cheating depending on how fast one of the players can move their fingers or believes the other party can. Palming one of 6 easily distinguishable pebbles and revealing it doesn’t have that problem and finding 6 distinctive pebbles is easy. My post#17 is really no trouble at all, and works perfectly as a die if either party accepts their own choice as random. [Previous page](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404.md?page=2) [Next page](https://boards.straightdope.com/t/how-to-create-a-random-number-generator-for-1-6-with-just-natural-supplies-in-the-wilderness/806404.md?page=4)