The best explaination of the Liskov Principle - by Allen Holub
You want to learn with really good examples why all inheritance is bad, and why you should think twice if you want to inherit in places or if you jump on the ship with the new tool/library/framework that forces you to inherit from it's base class. Watch the first 30 minutes https://vimeo.com/163860086 (exactly until 30:00).