Strategy Review

Here is a summary of all the strategies given for Chapters 2-5.

&In Strategy

When you have A&B as a GOAL

A&B GOAL

&In Strategy

When you have A&B as a GOALTry to prove A and B separately.

Then paste them together with &In.

A&B &I

A GOAL

B GOAL

If you have a sentence with the shape A&B,

&Out Strategy

4) A&B

If you have a sentence with the shape A&B,

then use &Out to obtain A and B.

&Out Strategy

4) A&B5) A 4 &O6) B 4 &O

>In Strategy

When you have A>B as a GOAL

A>B GOAL

>In Strategy

When you have A>B as a GOALMake A a PA and try to prove B.

When B is proven, A>B will follow from >In.

A>B >I

A PA:B GOAL

>Out Strategy

When your GOAL G is to the right of an >in an available line,

A>G

G GOAL

>Out Strategy

When your GOAL G is to the right of an >in an available line,

Make the antecedent A of that line a new GOAL.When A is proven, G will follow from >Out.

A>G

A GOALG >O

Negation Strategy

If you are stuck.

A GOAL -A GOAL

Negation Strategy

If you are stuck.Set the opposite of your GOAL as a PA,

and derive a contradiction.

A -O -A -I

-A PA:?&-?

A PA:?&-?

Choosing Contradictions

Avoid choosing A&-A as your contradiction.

-A PA

?&-? GOALA -O

Choosing Contradictions

Avoid choosing A&-A as your contradiction.

-A PA

A&-A BAD IDEAA -O

Choosing Contradictions

If a complex negation sentence is available...

-A PA

?&-? GOAL A -O

-(B&C)

Choosing Contradictions

If a complex negation sentence is available... it is a good idea to use it as part of a contradiction.

-A PA

(B&C)&-(B&C) GOOD IDEA A -O

-(B&C)

For more click here