One thing that makes the adventure of working in our field particularly rewarding, especially in attempting to improve the theory, is that... a chief criterion for the selection of a correct hypothesis... seems to be the criterion of beauty, simplicity, or elegance.

Everything that is not forbidden is compulsory.

I think also of my colleagues in elementary particle theory in many lands, and feel that in some measure I am here as a representative of our small, informal, international fraternity.

What is especially striking and remarkable is that in fundamental physics a beautiful or elegant theory is more likely to be right than a theory that is inelegant.

Planets are too dim to be detected with existing equipment, far away, except in these very special circumstances where they're seen by their gravitational effect

Of course the word chaos is used in rather a vague sense by a lot of writers, but in physics it means a particular phenomenon, namely that in a nonlinear system the outcome is often indefinitely, arbitrarily sensitive to tiny changes in the initial condition

I would recommend that skeptics devote even more effort than they do now to understanding the reasons why so many people want or need to believe.