A spectre is haunting the West – the spectre of Malthusianism. Talk of a food crisis has provoked commentators to claim that there are too many mouths to feed. In fact, despite some environmentalists’ claims that the crisis reinforces their belief in the natural limits of humankind’s ambitions, we already have enough food to feed all Earth’s people, and more.

The current crisis is doubtless a serious one. The market price of basic cereals has doubled within the last year, sparking unrest in Haiti, the Philippines, Egypt, Senegal, Bangladesh and elsewhere. Aid agencies are being forced to cut food aid across the globe, the World Bank has warned that 100m people could be pushed further into poverty, and UN Secretary-General Ban Ki Moon suggested that food riots pose a serious threat to political security in developing countries. Most starkly of all, 840m people worldwide suffer from malnutrition.

The causes of this crisis are complex. They include bad weather, rising fuel and fertilizer prices, and rising meat consumption, since it takes several kilos of grain to produce one kilo of meat, leading greens like George Monbiot to demand that we all become vegetarian. Biofuel production has undoubtedly had a severe effect, leading a UN Special Rapporteur to label it a “crime against humanity”. Certainly, the crisis has exposed the fundamental irrationality and environmentally unfriendly nature of biofuels once and for all.

More disturbingly, there has been a strong streak of Malthusianism in much of the commentary: the idea that there are simply too many mouths to feed. As CNN founder Ted Turner put it, “There’s too many people. That’s why we have global warming… because too many people are using too much stuff.” Once only a preserve of nutcases like the Optimum Population Trust (who want to cut world population by one to three billion), this idea has now been mainstreamed by green campaigners. The Independent must be particularly delighted, since its Environment editor argued four years ago that economic trends were “fulfilling the gloomy predictions of Thomas Malthus”.

Let us be quite clear about the real nature of the crisis: it is a crisis of affordability, not supply. The world already produces enough food to feed more than its current population. There is enough cereal alone to supply everyone in the world with 3,500 calories daily, well in excess of the healthy minimum of 2,500 – and this is before meat, vegetable, nut and bean production is taken into account. Global agriculture today produces 17 per cent more calories per capita than it did thirty years ago. People starve because they cannot afford food, not because there are too many mouths to feed. The food crisis is actually a poverty crisis: it exposes not the planet’s overpopulation but the precarious existence of billions of people for whom a rise in basic commodity prices spells ruin.

The fundamental reason why Malthus was proven wrong is that he systematically underplayed mankind’s capacity to enhance and transform nature to fulfil its needs and desires. That very idea is anathema in an age where environmentalists urge us to bow down to nature and respect the limits it imposes on us. But, put simply, there are more of us today, living healthier, better lives, because we got much better at producing food (among many other things) by introducing scientific techniques, fertilisers and mechanisation. Paul Erlich’s claim in The Population Bomb (1968) that hundreds of millions would starve to death in the late 1960s was confounded by the Green Revolution, the export of modern farming techniques and tools to the third world, particularly the Indian subcontinent.

Crucially, however, these productivity gains have been profoundly uneven and remain concentrated in the capitalist heartlands. While annual food production per capita is 1,230kg in the USA, it is 325kg in China and a mere 90kg in Zimbabwe. Put another way, farmers in countries with highly-developed agricultural sectors produce one to two million kilograms of cereal each; by contrast, of the world’s 3bn peasant farmers, those who benefited from the Green Revolution produce 10,000-50,000kg, but those excluded completely from new technologies produce only 1,000kg.

The underdevelopment of and lack of investment in agriculture in developing countries means that agricultural productivity growth has not kept pace with population growth – in Africa, for instance, the respective rates are two and three per cent. Argentina, the EU, and the USA produce 80 percent of world food exports, on which the poorer countries now depend – hardly any wonder, then, that the US shift to biofuel production has had such a dramatic effect on world-market prices.

This is compounded by perverse rich-country policies, such as the foisting of mono-cultural cash crops on developing countries, crops that have undermined soil fertility. Other problems include the huge domestic subsidies for agriculture, which make many poor-country farmers unable to compete, and the dumping of Western produce on poor countries in the form of food aid. The idea that the issue is one of distribution rather than supply is reinforced by the fact that food production has continued to grow even as the total land area under cultivation in Europe fell from 732m hectares in 1981 to 656 hectares in 2000 – because of a problem of oversupply. EU farmers were being paid to keep their land fallow – and now they are locked into ludicrous 10-year schemes that prevent them from reverting to food-production even though prices are now high.

The facts, then, have not changed since Amartya Sen published his influential 1981 book, Poverty and Famines, which showed that unjust socioeconomic and political structures cause famines, not food shortages. It should scarcely need pointing out that the prevailing economic system, where profit rather than need dictates the production and distribution of goods, is the real problem behind the crisis.

Rather than seeking to change this system (which admittedly shows little sign of being overthrown any time soon), attention is focusing on increasing poor-country agricultural productivity. The Alliance for a Green Revolution in Africa is a potentially promising development, seeking to bring much-needed investment, new seeds, fertiliser, technology and infrastructure to the continent. If it can genuinely empower African farmers rather than serving the interests of Western agribusiness, it may be worth supporting. But without being accompanied by more thoroughgoing structural change – such as the redistribution of land from rich to poor, the dismantling of Western subsidy regimes and the reform of international trade systems – the benefits are likely to accrue very unevenly, and may not address the fundamental problem of gross inequality and poverty that ultimately underlies malnutrition. The spectre of Malthusianism needs exorcising quickly.

David Willetts inherited a mouthful of a title when he became the Shadow Secretary of State for Innovation, Universities and Skill in July 2007. His official role is to coordinate the Conservatives’ policy on higher education, but his importance to the party stretches beyond this, as he is considered one of its leading intellects.

Any discussion with David (affectionately known as “two brains”) promises to be mentally stimulating, as he discusses the big issues of British politics and Conservative ideology. To the common man he might look every bit the archetypal Tory MP but he is far from fulfilling much of the stereotype. His views are moderate and he is clearly willing to challenge received wisdom in favour of brightening up the intellectual scene.

When I suggest that Gordon Brown’s current malaise might be the catalyst for Willetts’ return to government – he previously served in the Treasury under Nigel Lawson – he responds confidently: “I think that the Conservative party is in better shape than it”s been in for over a decade. People can sense that we are changing; they can sense that we are focusing on the issues that they worry about rather than an inward-looking debate that focuses on our own agenda.” For eleven years, Conservative ministers have been saying the same, generally to deaf ears, but now the message seems to resonate. The Conservatives under Cameron have enjoyed a healthy lead in the polls since the “Brown bounce” last summer, and it looks set to continue.

This does not mean, however, that Willetts is complacent. He is eager to be optimistic but makes the salient point that the Conservatives still have fewer MPs in Parliament now than Michael Foot did after the “disastrous” Labour election of 1983. He is a man who understands the uphill task ahead: “no one,” he cautions, “should be measuring the curtains for their departmental office just yet.”

It is still far too early to predict the outcome of the next general election, but most would certainly argue that it will be the first since 1992 in which the Tories will have a genuinely decent chance of winning. As might be expected of Willetts, he puts it all down to the fruition of new ideas. “There is a recognition that the political renewal of conservatism is also an intellectual renewal.” He castigates the old Tory view that ideas have no place in the political discussions in the “Dog & Duck” and is excited by the party’s willingness to re-engage in intellectual discussion.

I put to him, therefore, one of the most tricky questions in British politics, “What is conservatism?”. He is quick to stress that the creed has often changed in the party’s history (so much so one would suspect that “being pragmatic” is akin to “being conservative”) but that the debate is hindered by a false dichotomy. “We had,” he argues, “a conventional political debate in which Conservatives were the party of the market and Labour were the party of the state, but a hell of a lot of what matters to most people lies in between the two – the family, the neighbourhood or the community. This is what we mean by the phrase “non-state collective action.””

Willetts has much to say on how to incorporate economic game theory and even evolutionary biology into Conservative political thought. The general idea is that humans gain pleasure in the brain from being able to forge our own collective institutions, and therefore it serves an evolutionary purpose to allow the individual greater economic and political freedom. These hypotheses are still inchoate, but Willetts is willing to grapple with them and perhaps to provide answers out of left field.

When asked about his student days at Oxford, Willetts responds, “I am one of nature’s PPEists and I regard myself as in some ways still doing PPE.” Politics, it seems, is just an extension of university for a man who spent much of his time at Oxford founding societies and arranging meetings. Optimistically, he suggests that “students work harder now than when I was a student.” And after I regretfully correct his mistake, we move on to discussing Conservative policy on universities.

The “student experience” is as close as a buzz word as Willetts will allow himself, and he turns to this phrase when questioned about student funding. The party has called for a 2010 review of university funding so that the impact of top-up fees can be properly measured, but for now Willetts is most concerned with the quality of university life: “What I’m increasingly picking up on is that the quality of the student experience is something that students across the country raise with me more and more – how many essays you’re going to have to write, how accessible the academics are, how much academic feedback you’re going to get and how crowded the seminars are. You can only justify the fees that students are now charged if students are confident that the money is going into improving the student experience.”

Tony Blair kick-started the university funding debate with his policy that 50% of school leavers should be attending university, thus creating a requirement for extra funding. “I’m sceptical about these abstract targets,” says Willetts, “and we’ve just had some evidence that the percentage of young people going to university has only increased from 37.2 to 37.8 per cent.” He continues: “Your question shows what’s gone wrong with this target, which is that you get a debate about a target rather than a debate about the real world question “how do we ensure that more young people are going to university?” That is a real-world challenge and I’d rather focus on that than on abstract targets that Tony Blair plucked out of the air for effect.”

After our interview I would find it impossible to pigeonhole David Willetts. He understands that government should be realistic and yet believes that it only makes sense in the context of intellectual rigour. He is part of a party which is widely caricatured as “inertia personified” and yet he is keen to draw on the cutting edge of academic research. It’s clear that his days studying PPE at Christ Church have been significant in the making of the senior politician before me. He leaves me with an indication of why the place is so special to him: “There’s a great cartoon of a man sitting in a library, looking up, surrounded by books, and saying, “good God! for a moment then it all made sense.” I learnt about the men of the British Enlightenment at Oxford, and that mix of the cultural, the political and the philosophical is what I think politics is like when it’s at its best. And that’s what makes every day so stimulating as a politician.”