It is a pity that John A. Duley, in Correspondence (“Tough lessons for survival in hard academic times”, Nature 427, 13; 200410.1038/427013a), did not include Steven Weinberg's fourth “golden lesson” (Nature 426, 389; 2003) in his own list — namely, to learn some of the history of science.
If you look back further than 25 years, it becomes clear that relatively low pay for research scientists has been a feature of the profession since its earliest days.
The junior scientists who sailed on the research vessel Challenger 130 years ago, for example, were paid £200 a year, roughly equivalent to £7,000 (US$12,700) today (A. L. Rice, Arch. Nat. Hist. 16, 213–220; 1989), or less than 40% of the “poor salary” example given by Duley.
Albert Einstein did his most important science after hours while working at his ‘real job’ as a third-class patent clerk in the Bern patent office.
Gertrude Elion (who won the Nobel Prize in medicine in 1988) started working as an unpaid laboratory technician in the 1930s and only after proving herself could enjoy the “magnificent” sum of $20 a week.
Clearly if any of these and many other individuals had chosen their research paths “according to hard-headed economics”, as Duley advises, we would all be the poorer. To borrow Donna Summer's immortal words, a merchant banker “works hard for the money, so you better treat her right” — job satisfaction is not guaranteed even when the pay is good.
My own laboratory website lists three basic requirements for joining the group: an open mind, an interest in science for its own sake and a tolerable sense of humour. Disregarding the third idiosyncratic requirement, I would argue that students who fit the first two criteria should follow Steven Weinberg's advice to the letter.