3 ms·

Pix or it didn't happen. (No pix and it did happen, I suppose).

thaumasiotes 5y ago
> Pix or it didn't happen. (No pix and it did happen, I suppose). These two statements are opposites. What you want is this tautology p → q ⟺ ¬p ∨ q By which you can see that "pix or it didn't happen" is equivalent to "no pix implies it didn't happen".
- treasfdfs 5y ago
  Depends on what 'it' means, I was referring to 'it' being theft. Pix present => no theft happened, no pix => theft happened. It's xor rather than logical implication.
  - thaumasiotes 5y ago
    p ⊕ q is still not equivalent to ¬p ∧ ¬q, though in this case they're just unrelated rather than being opposites.
    - treasfdfs 5y ago
      It's (¬p ∧ q) ∨ (p ∧ ¬q) meaning 'either one or the other' ((no pics and theft) or (pics and no theft)). So its boolean inequality which is xor. Pedantry is kewl.
      - thaumasiotes 5y ago
        > It's (¬p ∧ q) ∨ (p ∧ ¬q) meaning 'either one or the other' ((no pics and theft) or (pics and no theft)). So its boolean inequality which is xor. This is the definition of xor, but it does not appear to be related to any of your previous comments. > Pedantry is kewl. OK.
        sillysaurusx 5y ago
        How are you writing those symbols so easily?
        thaumasiotes 5y ago
        I search for them, with searches like "unicode vee"[1] which brings up https://en.wikipedia.org/wiki/Descending_wedge https://en.wikipedia.org/wiki/Descending_wedge . Then I copy and paste. This mirrors my strategy of producing letters with diacritics by going to the wikipedia page for the diacritic and copying from the big table of Every Letterform Using This Diacritic that they all have. These three pages are especially useful: http://xahlee.info/comp/unicode_arrows.html http://xahlee.info/comp/unicode_arrows.html https://www.johndcook.com/blog/math_symbols/ https://www.johndcook.com/blog/math_symbols/ https://en.wikipedia.org/wiki/Blackboard_bold https://en.wikipedia.org/wiki/Blackboard_bold [1] "vee" because the LaTeX command is \vee. That said, "unicode oplus" didn't work well.

> Pix or it didn't happen. (No pix and it did happen, I suppose). These two statements are opposites. What you want is this tautology p → q ⟺ ¬p ∨ q By which you can see that "pix or it didn't happen" is equivalent to "no pix implies it didn't happen".

treasfdfs 5y ago
Depends on what 'it' means, I was referring to 'it' being theft. Pix present => no theft happened, no pix => theft happened. It's xor rather than logical implication.
- thaumasiotes 5y ago
  p ⊕ q is still not equivalent to ¬p ∧ ¬q, though in this case they're just unrelated rather than being opposites.
  - treasfdfs 5y ago
    It's (¬p ∧ q) ∨ (p ∧ ¬q) meaning 'either one or the other' ((no pics and theft) or (pics and no theft)). So its boolean inequality which is xor. Pedantry is kewl.
    - thaumasiotes 5y ago
      > It's (¬p ∧ q) ∨ (p ∧ ¬q) meaning 'either one or the other' ((no pics and theft) or (pics and no theft)). So its boolean inequality which is xor. This is the definition of xor, but it does not appear to be related to any of your previous comments. > Pedantry is kewl. OK.
      - sillysaurusx 5y ago
        How are you writing those symbols so easily?
        thaumasiotes 5y ago
        I search for them, with searches like "unicode vee"[1] which brings up https://en.wikipedia.org/wiki/Descending_wedge https://en.wikipedia.org/wiki/Descending_wedge . Then I copy and paste. This mirrors my strategy of producing letters with diacritics by going to the wikipedia page for the diacritic and copying from the big table of Every Letterform Using This Diacritic that they all have. These three pages are especially useful: http://xahlee.info/comp/unicode_arrows.html http://xahlee.info/comp/unicode_arrows.html https://www.johndcook.com/blog/math_symbols/ https://www.johndcook.com/blog/math_symbols/ https://en.wikipedia.org/wiki/Blackboard_bold https://en.wikipedia.org/wiki/Blackboard_bold [1] "vee" because the LaTeX command is \vee. That said, "unicode oplus" didn't work well.