LSAT Tip: The Word "Unless."

The word “unless” doesn’t guarantee a thing.

“You can’t ride this ride unless you’re x feet tall” does not mean that if you’re x feet tall you can ride the ride. “You won’t see a drop in your blood pressure unless you limit your sodium intake” doesn’t mean that if you limit your sodium intake you’ll see that drop in blood pressure. “You can’t go on the school trip unless you hand in the permission slip” doesn’t mean you can go on the trip if you hand in the slip. “Unless” sets up a requirement. No slip, no trip. No decrease in sodium, no reduction in blood pressure. The word “unless” provides enough information to draw a conclusion if the condition is not satisfied. It tells you nothing at all about anything if the condition is satisfied. I think a reason why the LSAT is challenging is because logic doesn’t exactly line up with the way words are used in everyday life. If you’re told that you can’t go on the trip unless you hand in a permission slip, you’d be reasonable to conclude you can go on the trip once it’s handed in. Careful. The LSAT is waiting for you to make that mistake.