• Lafari@lemmy.worldOP
    21·
    10 months ago

    If car, then vehicle = true

    Car if and only if vehicle = true.

    Is this correct?

    Therefore “If A then B” = “A if and only if B” (or “If B then A” = “B if and only if A”)?

    • zenharbinger@lemmy.world
      5·
      10 months ago

      B can still be true when a is false. iff means that b can only be true when a is true.

      Also, the equivalent statement is.

      vehicle if and only if car.

      not

      car only if vehicle

      since a truck is a vehicle, the statement is false.

      Somewhat wrong above:

      A B a iff b

      T T T

      T F F

      F T F

      F F T

      look online for truth tables.

    • Ep1cFac3pa1m@lemmy.world
      32·
      10 months ago

      You’d have to firm up your definition of car and vehicle before you could decide that one. Does a hot wheels car count as a car? Does a vehicle have to be large enough to move people or freight?