Knowing how to diagram conditional claims is essential for every scored section of the LSAT. In LSAT Logical Reasoning, you have to diagram conditional claims very often with Must Be True, Must Be False, Could Be True, Sufficient, Necessary, Flaw, Parallel, and Parallel Flaw question types. In LSAT Logic Games, you’ll make some very nasty mistakes by incorrectly diagraming conditional rules. Finally, in LSAT Reading Comprehension, main points can be conditional, and many other question types will also depend on your ability to diagram.

All diagramable questions have very tempting sucker choices. This is because diagraming mistakes are easy to predict. So, an incorrect anticipation will probably show up in your answer choices. This makes diagramable questions pretty difficult. However, anyone who can follow a recipe can eventually become a diagraming master.
With about two months to go before the October LSAT we thought it would be fun – and not at all terrifying – to give you an opportunity to test your diagraming skill level. If you manage to diagram all of the following conditional claims correctly, you will win a very awesome prize: our respect and admiration.

LSAT Diagraming Level 0: If-Then Claims

Okay let’s start you off with something very profound and easy to diagram.

1. If you grew a beard, then you stopped shaving.

Key: If-then claims are easy!

LSAT Diagraming Level 1: Sentence Order

Knowing how sentence order affects diagraming separates the true beginners from those who are just a wee bit better.

2. Every Montreal resident loves poutine.

3. A love of poutine is something all residents of Montreal have.

4. Jerry must be selected, for Newman to be selected.

Key: Sentence order doesn’t matter, keywords do.

LSAT Diagraming Level 2: Only, Only if, The Only

You need to understand how to deal with conditional claims that use the word “only.” If you can diagram the following conditional claims correctly, then you’re on your way to LSAT diagraming mastery.

5. You can cross the bridge, only if you answer the riddle.

6. Only boys are allowed in the He-man Women Haters Club.

7. The only thing we have to fear is fear itself.

Key: You can’t treat all “only” claims equally.

LSAT Diagraming Level 3: Unless, Until, Without

The diagraming indicators, “unless,” “until”, and “without” are often featured in more difficult diagramable LSAT questions. If you can correctly diagram the next three conditional claims, then I give you permission to feel good about yourself.

8. Unless we catch the weasel, the birthday party will fail.

9. You can’t please your significant other, until you’ve read Cosmo.

10. The Dude would have been better off without Walter around.

Key: Replace “unless,” “until,” and “without” with “if not.”

LSAT Diagraming Level 4: Mastery

LSAT test-makers can use negation to make your diagraming life more difficult. If you can diagram the following claims correctly, then you might just be an LSAT diagraming master.

11. The birthday party will fail, unless we catch the weasel and find the cake.

12. According to some experts, to grow a beard you must stop shaving. If, but only if these experts are right, then beards are simple to grow.

13. No self-respecting bibliophile wouldn’t accept this first edition.

Key: Be comfortable with complex negation.

Don’t forget that you also have to know how to combine conditional claims. So, knowing how to diagram conditional claims is necessary, but not sufficient for your LSAT success. Yes, that last sentence is diagramable.

Good luck diagraming on the October LSAT!

Answers:

1. If you grew a beard, then you stopped shaving.
GB → Not-S
S → Not-GB

2. If you are a Montreal resident, then you love poutine.
MR → LP
Not-LP → Not-MR

3. If you are a Montreal resident, then you love poutine.
MR → LP
Not-LP → Not-MR

4. If Newman is selected, then Jerry is selected.
N → J
Not-J → Not-N

5. If you can cross the bridge, then you answered the riddle.
CB → AR
Not-AR → Not-CB

6. If you are allowed in the He-man Women Haters Club, then you are a boy.
AC → B
Not-B → Not-AC

7. If we have to fear it, then it is fear.
HF → F
Not-F → Not-HF

8. If we do not catch the weasel, then the birthday party will fail.
Not-CW → BF
Not-BF → CW

9. If you haven’t read Cosmo, then you cannot please your significant other.
Not-RC → Not-PSO
PSO → RC

10. If Walter were not around, the Dude would be better off.
Not-W → D+
Not-D+ → W

11. If we do not catch the weasel or we do not find the birthday cake, then the birthday will fail.
Not-CW or Not-FBC → BF
Not-BF → CW and FBC

12. Growing a beard requires that you stop shaving if and only if growing a beard is simple.
(GB →Not-S) ←→ Simple
(can GB and S) ←→ Not Simple

13. If you are a self-respecting bibliophile, then you would accept this first edition.
SRB → AFE
Not-AFE → Not-SRB