Only if and unless

"Only if" names something needed: "you may swim only if you wear a cap" means no cap, no swimming - not that a cap lets you in. "Unless" means "if not".

Depth 1 · Foundation

You can say what "only if", "if and only if" and "unless" claims rule out, and turn each into a plain if-then claim.

Depths of understanding

1
Foundation
You can say what "only if", "if and only if" and "unless" claims rule out, and turn each into a plain if-then claim.
Opens after
Needed and enough"Only if" names something needed, and "if and only if" something both needed and enough.

Your path here

What's still between you and Only if and unless, depth 1, in the order you can learn it.

1ClaimDepth 1 · Foundation · Logic
2ArgumentDepth 1 · Foundation · Logic
3Conditional statementsDepth 1 · Foundation · Logic
4Needed and enoughDepth 1 · Foundation · Logic
5Only if and unlessDepth 1 · Foundation · Logic

Builds on

Needed and enough"Only if" names something needed, and "if and only if" something both needed and enough.

Opens up

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