Anyone in animation should be able to rattle off Frank & Ollie's 12 Principles of Animation. Google it.
However, what most folks might not realize is John Lasseter presented "Principles of Traditional Animation Applied to 3D Computer Animation" at SIGGRAPH way back in 1987! He sought to bring humanity and artfulness into the emerging art form known as digital animation.
That is why John is THE MAN.
read the paper here