People care more for themselves when they contribute to the system.

There must be consistency in direction.

A goal without a method is nonsense.

There is no substitute for knowledge.

Experience by itself teaches nothing... Without theory, experience has no meaning. Without theory, one has no questions to ask. Hence, without theory, there is no learning.

We should be guided by theory, not by numbers.

When asked what single event was most helpful in developing the Theory of Relativity, Albert Einstein replied, "Figuring out how to think about the problem".