# A Stupidly Hard Dog Logic Puzzle

**URL:** <https://forum.beeminder.com/t/a-stupidly-hard-dog-logic-puzzle/5252>\
**Category:** Buzzles\
**Created:** [April 22, 2019, 9:56pm UTC](https://forum.beeminder.com/t/a-stupidly-hard-dog-logic-puzzle/5252 "2019-04-22T21:56:12Z")\
**Posts on this page:** 1\
**Showing post:** 17

<div class="post-metadata">

**Author:** ![dreev](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.beeminder.com/dreev/32/4311_2.png) [@dreev](https://forum.beeminder.com/u/dreev)\
**Post date:** [May 2, 2019, 7:45pm UTC](https://forum.beeminder.com/t/a-stupidly-hard-dog-logic-puzzle/5252/17 "2019-05-02T19:45:38Z")

</div>

> [@drtall](#):
>
> once I’ve specified the infinite sequence I care about, it has probability 0 of happening even though we already agreed it is possible. I don’t understand how this is so.

Yeah, it sounds contradictory but is pretty standard! It’s “possible” to flip a fair coin heads an infinite number of times in a row in the sense that that is one of the possible outcomes of an infinite list of coin flips. To get the probability we have to take the limit of 1/2^n as n goes to infinity and the answer to that is zero.

---

_[View the full topic](https://forum.beeminder.com/t/a-stupidly-hard-dog-logic-puzzle/5252)._