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by dinkleberg 1597 days ago
Am I wrong in thinking that some of these answers while correct, are correct for the wrong reason?

I know this is pedantic, but not sure if this is just them explaining it oddly or if I'm thinking about it incorrectly.

[Spoilers?]

It says:

Yellow. It is not necessary to turn this card over. The card is showing yellow, therefore, we already know that the rule is upheld. The rule only requires that when a circle appears it is paired with yellow. We already have the requisite yellow, so there's no problem even if there's a circle on the other side of the card.

A therefore B doesn't mean B therefore A. We don't flip over the yellow card because nothing tells us that a yellow card needs a circle on the other side. Not because it is yellow and we know that the circle is on the other side, because we don't know.

1 comments

Their explanation seems fine to me, if a little awkward.

> We don't flip over the yellow card because nothing tells us that a yellow card needs a circle on the other side. Not because it is yellow and we know that the circle is on the other side, because we don't know.

If a card is yellow, it doesn't matter what is on the other side, so we don't have to check it. Either it is a circle, in which case the rule is upheld, or it is any other shape, in which the rule is still upheld.

In the case of the red card, it DOES matter what is on the other side, as if it is a circle the rule is broken.