Understanding how contrapositive work I want to understand contrapositive clearly. I'll start by saying: "If it is sunny, then there is light". The statement is true. But now consider the contrapositive: " If there is no light then it is not sunny".  The contrapositive is false because you could create light with a flashlight.
What is wrong here?

Read your correct contrapositive again:

If there is no light then it is not sunny.

That's true - it's equivalent to the first statement. You could create light with a flashlght, but then there would be light.
What

you could create light with a flashlight.

tells you is that the original true statement is not "if and only if". The converse

If there is light then it is sunny

is false.
