Teachers are effective only when they help their students become independent learners. Yet not until teachers have th...

Naz on December 12, 2014

Alright let's diagram.

"Teachers are effective only when they help their students become independent learners."

P1: TE ==> HSIL
not HSIL ==> not TW

"not until teachers have the power to make decisions in their own classrooms can they enable their students to make their own decisions."

P2: HSIL ==> PMD
not PMD ==> not HSIL

"Students' capability to make their own decisions is essential to their becoming independent learners."

P3: IL ==> CMOD
not CMOD ==> not IL

"Therefore, if teachers are to be effective, they must have the power to make decisions in their own classrooms."

C: TE ==> PMD
not PMD ==> not TE

We are asked to see what cannot be true of teachers who have enabled their students to make their own decisions: "HSIL"

Well, "P2" tells us that HSIL ==> PMD.

Answer choice (E) states: "They do not have the power to make decisions in their own classrooms."

(E): not PMD

Thus, according to "P2," answer choice (E) cannot be true because if a teacher enables their students to make their own decisions, then we know that the teacher has the power to make decisions in their own classroom.

Hope that clears things up! Please let us know if you have any other questions.

Anna20 on August 13, 2020

Is until diagrammed in the same way as unless - i.e. until precedes the necessary and then you negate? I diagrammed the second sentence as PMD ==> HSIL - which is obviously wrong!

Thanks so much for setting out the above - really helpful here.

Victoria on August 13, 2020

Hi @Anna2020,

You are correct! "Unless," "without," and "until" are all diagrammed the same way.

Keep up the great work and please let us know if you have any further questions.