Blue skies versus applied research
Should science be about discovery for its own sake or about solving the most serious problems of the day?
It's a question that's almost as old as science itself. The earliest reference I could find comes from Plato's Republic, where Socrates takes Glaucon to task for worrying about whether Astronomy is a worthwhile pursuit.
But it's also a question that's got today's scientists arguing amongst themselves.
The former chief scientist Sir David King sparked off the row when he said it was "astonishing" that we were spending so much time and money on the Higgs Boson when there were much more pressing problems like climate change and environmental degradation to address.
His timing - he made the speech on the day the Large Hadron Collider was switched on - also seemed designed to provoke.
And what a reaction he got. It takes quite a lot to get Lord Rees, the president of the Royal Society, riled up, but he branded Sir David's comments both "misguided" and "mistaken".
Perhaps more worrying has been the steady swing of the funding pendulum towards applied research. The government has been rightly applauded for a big increase in the science budget, but increasingly ministers - and the Treasury - have emphasised tangible applications and quantifiable benefits.
Of course, there's nothing wrong with wanting to see a return on investment, or on insisting that money is efficiently spent. But 'picking winners' is a fool's game.
As Sir Chris Llewellyn Smith (the man who commissioned the LHC) says, it's not a zero sum game: you must have both blue skies and applied research.