HACKER Q&A
📣 xanderlewis

Are there any good sources of randomness in the human body?


Suppose I wanted to generate a 1 or a 0 with equal probability, and I don’t have access to anything other than my own conscious experience. No coins, no timers, no cameras, no thermometers — nothing. Just sitting in an empty, windowless room. How can I achieve this? I want to be able to generate a genuinely random (that is, no memorising a PRNG algorithm!) result at least once every ten minutes. Any ideas?


  👤 sebg Accepted Answer ✓
Did you see this discussion from a few years ago?

=> https://news.ycombinator.com/item?id=4508980

Might be helpful to think through.

This reddit post also has a few interesting tidbits:

https://www.reddit.com/r/askscience/comments/15vnpu/is_it_po...


👤 dieselgate
Open ended question but things that came to me are like "scratch your head and count the number of hairs that fall" or "number of blinks per duration" and see if it's even/odd. This is keeping in mind the title and focusing on the body

👤 fakamoto
Interesting question. I dont know the answer, but ive seen daniel negreanu (professional poker player) making decisions that require randomness with a personal method using his mind. I dont know how he does it, or if its really random, but thats something.

👤 pants2
Perhaps you could stare at a blank wall and identify the direction or other property of the 'floaters' that appear in your vision.

👤 schwartzworld
Close your eyes, spin around until you lose your sense of direction, open your eyes. Your direction will be pretty close to random.

👤 neontomo
Pick a word that you like, count the letters on your fingers, even is 0, odd is 1. Choose a longer word to make it harder to predict length.

For example, "sesquipedalian" is 14 letters, which even, which is 0. Pick a new word to repeat.


👤 paulkrush
Listen to the internal sounds of your body and find something that can be compared against a counter in your head. Passing a finger along your skin slowly will jump at random intervals. Can two people trigger each other?

👤 vunderba
Stare into space as long as you can without blinking, internally, count the interval until when you're forced to blink. Modulo by 2 to get a zero or one. Repeat as necessary.

👤 paulkrush
Guess too precise of a measurement, find a median, and use over under.