• 0 Posts
  • 13 Comments
Joined 1 year ago
cake
Cake day: July 5th, 2023

help-circle
  • I’m not able to find it again, so it may be entirely bunk, but I remember reading something about the Japanese during early interactions having a stereotype that Europeans didn’t bathe. Obviously this contact was past the medieval stages, but then that makes me ask “Did hygiene become less popular later?”

    So, now I’m curious whether this memory is:

    A) Pop culture contamination/made up whole cloth, i. e. an author who believed medieval people didn’t bathe and extrapolated it to the 1500s.

    B) True, and hygiene did become less popular with Europeans (seems unlikely).

    C) Born of the fact that people who have been at sea for so long are not a good representation of overall hygiene.

    D) Born from a another factor unrelated to hygiene, but perceived as such by the Japanese. Maybe differences in sweating or diet or something.

    E) Some combination of the above.












  • Zero divided by zero is undefined. In that it literally does not meet the definition of division (from a mathematical perspective.)

    This is a bit tricky because the reason that 0/0 is undefined is separate from why any other number divided by zero is undefined.

    If I divide 6 by 0, there’s no number I can multiply by zero to get back to 6. Since I can’t get back to the 6, this is undefined.

    If I divide 6 by 2, I get 3. And I can multiply 2 by 3 to get 6. Now it’s genuinely important that there is no other number I can multiply 2 by to get 6. There has to be a single unique result for both the division and the going back via multiplication.

    Now, if we assume 0/0 = 1, that is fine. And I can multiply 1 times 0 to get back to 0. Checks out so far. However, 1 isn’t unique in getting back to 0. If I try 5 x 0, I get 0. Which, by the rules of division should mean that 0/0 = 5. Which clearly it wouldn’t.

    So zero divided by zero is undefined because there is an infinite amount of numbers that would get me back to zero.