PT 34 Section 2 #10

[nooyyllib]

I am not quite sure what the difference between A and D is.  why is D the answer and not A?

[KaplanLSATInstructor]

It's formal logic:

(A) says that ALL students with disabilities have special needs:

Disab. --> Needs

(D) says that ONLY students with disabilities have special needs:

Needs --> Disab.

The argument says that the school is violating the charter. Why? Because the charter requires students with special ed. needs, yet that school has no learning disabled students.

In a formal logic structure, the author is saying: If you have no students with disabilities, that means you don't have anybody with special ed. needs. (No disab --> No Spec. needs.) The contrapositive of this statement is the correct answer: (D).

Try to see this argument as flawed. Why does the author feel that the school has no special ed students? Because they are none that are learning disabled! As if you have to have a learning disability to have special ed needs -- as if nobody else could have special ed needs. This is not to say that EVERYONE with a learning disability has special ed needs (as (A) suggests), but that ONLY students with a learning disability could possibly have those needs, and noone else.

HTH

- Chris

[KaplanLSATInstructor]

It's all about formal logic.

The argument is that the school doesn't have any students with special ed needs because it has no students with learning disabilities. In formal logic terms, the author is saying that if a school doesn't have students with learning disabilities, then none of the students have special ed needs -- as if nobody else but learning disabled students would have special ed needs.

The formal logic is: No disab --> no special ed
Contrapositive: special ed --> disab.

The author is assuming that nobody but learning disabled students have special ed needs -- as if one NEEDED to be learning disabled in order to have special needs.

(A) reverse the logic, saying that EVERYONE who has a learning disability has special ed needs:

Disab --> special ed.

But that's not the author's point. The author is assuming that anyone who has special ed needs must be disabled, but not necessarily the other way around.

(D) gets the logic right, saying that ONLY those with a learning disability could have special needs:

Special ed --> Disab.

This answer gets to the author's idea that nobody else could have special ed needs -- only those with a learning disability.

HTH

- Chris