Classical Logic Let's start with the notion that you cannot both have a cake and eat it, too. If you eat it, you no longer have it uneaten. Likewise, it's not possible for an object to be all red and all green at the same time. When ingredients become a cake, those ingredients are transformed by the human agency of baking.
Every elephant is an animal.
The widest class depicted above is Objects, subsuming all the others. Cakes are objects, but they are not animals, and they are not capable of reason. If you believe that Elephants can think, then I've drawn this diagram incorrectly, since Elephants have been excluded from the sub-group of Animals who are able to think. The purpose of studying classical logic is to deal with such questions. It is often the case that we need to speak of some members of a class, rather than every member.