Engineers think that equations approximate the real world. Scientists think that the real world approximates equations. Mathematicians are unable to make the connection.

The graduate with a science degree asks, "Why does it work?"
The graduate with an engineering degree asks, "How does it work?"
The graduate with an accounting degree asks, "How much will it cost?"
The graduate with a liberal arts degree asks, "Do you want fries with that?"

What is the difference between Mechanical and Civil Engineers? Mechanical Engineers build weapons, Civil Engineers build targets.