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If Nazi, then fascist = true
Fascist, if and only Nazi = not true
If car, then vehicle = true
Vehicle if and only if car = not true
I used the bananas are fruits analog but your one works well too!
I just figured with Lemmy’s interest in politics it seemed like an obvious example. I threw in the car because I didn’t want to be that guy who makes everything about nazis…
Yeah careful with that, the logic example Nazis will be all over you if you don't mix it up some.
Not everything is about Nazis, Boinkage, geez…
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")?
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.
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?
Don't confuse this guy with ontological questions.
This is straight truth table level stuff.