Orthogonal Quotes

“Easy!,” you think. “Gently lower the collective pitch lever and you’ll descend gracefully to the ground, a hero.” However, when you try it, you discover that life isn’t that simple. The helicopter’s nose drops, and you start to spiral down to the left. Suddenly you discover that you’re flying a system where every control input has secondary effects. Lower the left-hand lever and you need to add compensating backward movement to the right-hand stick and push the right pedal. But then each of these changes affects all of the other controls again. Suddenly you’re juggling an unbelievably complex system, where every change impacts all the other inputs. Your workload is phenomenal: your hands and feet are constantly moving, trying to balance all the interacting forces.
Helicopter controls are decidedly not orthogonal.”
― Andy Hunt, The Pragmatic Programmer: From Journeyman to Master