Euler diagrams?

1.

No human who is thorough is wrong.

All humans who are wrong are lazy.

Therefore, no humans who are lazy are thorough.

i) A is thorough implies A is not wrong

ii) A is wrong implies A is Lazy

Try to conclude:

A is Lazy implies A is not thorough - - - NOT TRUE

here's the reason: Both i) and ii) above goes only 1 way (forward)

i) is equivalent to i)' A is wrong implies A is not thorough

The "A is wrong" set is a small subset of "A is not thorough"

but ii) DOES NOT mean: A is lazy implies A is wrong !!!

The "A is wrong" set is a small subset of "A is lazy"

So the "A is not thorough" set and "A is lazy" set do not contain each other, or are not subset of each other!

2.

All places where books are present are places where there is a library.

The school is a place where books are present.

Therefore, the school is a place where there is a library.

A a place with books implies A a place with library

A a school implies A a place with books

so A a place with library

Therefore, the school is a place where there is a library.

is CORRECT

3.

All pigs are animals.

All animals can jump.

Therefore, all pigs can jump.

A a pig implies A an animal

A an animal implies A can jump

so

A a pig implies A can jump

Therefore, all pigs can jump. is CORRECT