The election of a US president almost always seems like a crossroads, but the choice to be made on 4 November feels unusual, and daunting, in its national and global significance.

Science and the research enterprise offer powerful tools for addressing key challenges that face America and the world, and it is heartening that both John McCain and Barack Obama have had thoughtful things to say about them. Obama has been more forthcoming in his discussion of research goals (see Nature 455, 446–449; 2008), but both have engaged with the issues. McCain deserves particular credit for taking a stance on carbon emissions that is at odds with that of a significant proportion of his party.

There is no open-and-shut case for preferring one man or the other on the basis of their views on these matters. This is as it should be: for science to be a narrow sectional interest bundled up in a single party would be a terrible thing. Both sides recognize science's inspirational value and ability to help achieve national and global goals. That is common ground to be prized, and a scientific journal's discussion of these matters might be expected to stop right there.

The core values of science are those of open debate within a free society that have come down to us from the Enlightenment.

But science is bound by, and committed to, a set of normative values — values that have application to political questions. Placing a disinterested view of the world as it is ahead of our views of how it should be; recognizing that ideas should be tested in as systematic a way as possible; appreciating that there are experts whose views and criticisms need to be taken seriously: these are all attributes of good science that can be usefully applied when making decisions about the world of which science is but a part. Writ larger, the core values of science are those of open debate within a free society that have come down to us from the Enlightenment in many forms, not the least of which is the constitution of the United States.

On a range of topics, science included, Obama has surrounded himself with a wider and more able cadre of advisers than McCain. This is not a panacea. Some of the policies Obama supports — continued subsidies for corn ethanol, for example — seem misguided. The advice of experts is all the more valuable when it is diverse: 'groupthink' is a problem in any job. Obama seems to understands this. He tends to seek a range of opinions and analyses to ensure that his own opinion, when reached, has been well considered and exposed to alternatives. He also exhibits pragmatism — for example in his proposals for health-care reform — that suggests a keen sense for the tests reality can bring to bear on policy.

Some will find strengths in McCain that they value more highly than the commitment to reasoned assessment that appeals in Obama. But all the signs are that the former seeks a narrower range of advice. Equally worrying is that he fails to educate himself on crucial matters; the attitude he has taken to economic policy over many years is at issue here. Either as a result of poor advice, or of advice inadequately considered, he frequently makes decisions that seem capricious or erratic. The most notable of these is his ill-considered choice of Sarah Palin, the Republican governor of Alaska, as running mate. Palin lacks the experience, and any outward sign of the capacity, to face the rigours of the presidency.

The Oval Office is not a debating chamber, nor is it a faculty club. As anyone in academia will know, a thoughtful and professorial air is not in itself a recommendation for executive power. But a commitment to seeking good advice and taking seriously the findings of disinterested enquiry seems an attractive attribute for a chief executive. It certainly matters more than any specific pledge to fund some particular agency or initiative at a certain level — pledges of a sort now largely rendered moot by the unpredictable flux of the economy.

This journal does not have a vote, and does not claim any particular standing from which to instruct those who do. But if it did, it would cast its vote for Barack Obama.