My papers tend to have the authors listed in alphabetical order. Why? Because I am persuaded that this is, as Winston Churchill said in another context (he was speaking of democracy), "the worst system in the world, except for all the others"; for further discussion see Nature 387, 831 (1997); ibid 388, 320 (1997). In recent articles I try to follow the practice of including a phrase detailing each author's contribution to the work; see Nature 399, 393 (1999).

On the scientific method:
"Nous avons trois moyens principaux : L'observation de la nature, la réflexion et l'expérience. L'observation recueille les faits, la réflexion les combine, L'expérience vérifie le résultat de la combinaison. Il faut que l'observation de la nature soit assidue, que la réflexion soit profonde, et que l'expérience soit exacte."
Denis Diderot, Pensées sur l’interprétation de la nature (1753) [English translation]

"The truth always turns out to be simpler than you thought. What we need is imagination, but imagination in a terrible strait-jacket. We have to find a new view of the world that has to agree with everything that is known, but disagree in its predictions somewhere... And in that disagreement it must agree with nature. If you can find any other view of the world which agrees over the entire range where things have already been observed, but disagrees somewhere else, you have made a great discovery."

Richard Feynman, The Character of Physical Law, Chapter 7, "Seeking New Laws" (1965)