The Government have promised that they would never, under any circumstances, subsidise nuclear power. Ed Davey, the Coalition Secretary of State for the Department of Energy and Climate Change, has stated that "There will be no blank cheque for nuclear – unless they are price competitive, nuclear projects will not go ahead."

However, the Coalition Energy Minister John Hayes, is now considering a major U-turn in energy policy by giving a blank cheque to nuclear by "underwriting" construction cost over-runs. This is despite the fact that the key to nuclear is its spiralling cost over-runs.

There are two nuclear reactors being built in Western Europe at the moment, one in Finland and one in France, and both are hugely over-cost and over-time. Both use the same technology as is proposed for the UK, the European Pressurised Reactor supplied by the French company Areva.

The Finnish reactor was planned to go online in early 2009, but the Finns are now crossing their fingers and hoping to complete around late 2014. Priced at €3bn, the reactor is now costed at €6bn and rising. Because of this, the Finns are in a billion-euro legal battle with the French nuclear construction firm Areva over who pays these extra costs.

And things are no better in France. Here, the builder, EDF, the company that would build in the UK, forecast the reactor would be complete this year, but time-scales keep slipping and they now say they hope to complete around 2016. Originally priced at just over €3bn, their reactor is also currently estimated at €6bn and rising.

Whatever one's view of the risks and benefits of nuclear energy, it is clear that construction cost over-runs are highly likely. The taxpayer and consumer must not end up footing a multi-billion pound bill for what seem to be inevitable nuclear construction cost over-runs.

Dr Paul Dorfman, University of Warwick

Dr David Toke, University of Birmingham

Professor Andy Stirling, University of Sussex

Dr Nick Eyre, University of Oxford

Professor Tom Burke, Visiting Professor, Imperial and University Colleges

Jeremy Leggett, Professor Peter A Strachan, The Robert Gordon University, Aberdeen Business School

Andrew Warren, Director, Association for the Conservation of Energy

Professor Brian Wynne, University of Lancaster

Time to study the lessons of the Great War

David Cameron's wish to commemorate the outbreak of the Great War in 1914 may have excellent results, so long as it does not result in yet more sentimental wallowing in memories of the Western Front and its horrors, which the British already indulge in annually.

In 2014 there should be a great national inquest on the causes of the war. Let us systematically and passionately look at both the long-term and short-term origins of the immense catastrophe, and see what we have learned, what we need to learn still, and what we have perhaps forgotten.

Let us, in renewed partnership with the other once-belligerent nations, devote ourselves once more to furthering peace and law and goodwill. And we might also ask ourselves if the lessons of 1914 are all that we need to learn: are there not new dangers in this century which are just as dangerous as militarism, navalism, nationalism and imperialism were a century ago?

Let us use the centenary to rededicate ourselves to building a world order of peace and justice: it is a mission that is still very far from being accomplished.

Professor Hugh Brogan

Department of History, University of Essex, Colchester

Osborne: a 'Taliban' writes

The Chancellor "smears all of us who care about the future" writes Mark Lynas in his very clear appraisal of sustainable energy (Voices, 19 October). Indeed he does, but Mark suggests that only the large pressure groups and green industries are offended.

Well, I am offended! As someone who tries to use public transport wherever he can, who has insulated his home beyond recommended standards, who switches off electrical appliances, and who recycles all that he can, I feel I am doing my bit for a greener future as well. I never thought I'd ever see myself described as a member of the Taliban: I even educated my daughter.

Yet again, we are clearly not "all in this together". The sooner our Chancellor starts living on this planet the better.

Christopher R Bratt

Arnside, Cumbria

So George Osborne was unwilling to pay Virgin the extra £120 for his first-class ticket. This is but a drop compared with the billions of losses his economic policy is inflicting on the UK economy and the unnecessary suffering that has resulted.

If swearing at a police officer merits resignation, then surely the alleged behaviour of our Chancellor, both in and out of that railway carriage, is much worse.

Peter Rowberry

Saxmundham, Suffolk

Plebeians, 2: Andrew Mitchell and George Osborne, 0.

Dominic Shelmerdine

London, W8

Passport to the top of the class

Dominic Lawson (16 October) warns against an obsession with class, particularly in the education system, and argues that because public schools supply 33 per cent of all students with three A-grade A-levels it's entirely appropriate that they take a far larger proportionate share of places at the best universities. Offering such places to state school applicants would be wrong in principle and foolish, nay dangerous, in practice, as state school pupils with lesser qualifications might be miserable or even suicidal.

Thank heavens the patrician classes remain solicitous for the welfare of the plebs.

People who send their children to public school do so in order to ensure their offspring have a very significant advantage over those whose parents are unable to afford to do so. It is the most significant advantage a parent can buy, and usually secures entrance into one of the best universities, where, of course, the tuition fees are far less than the school fees paid to secure admittance. This system remains the foundation of privilege, generation after generation, in the UK, and the benefits last a lifetime.

Naturally those who enjoy such advantages will denounce any attempt to challenge their privilege by those trying to level the playing field a little.

Martin Callaghan

London W5

Church needs a new council

Terence Duffy's suggestion (letter, 18 October) that there should be a Third Vatican Council is probably the only way in which the Catholic Church's current problems can be resolved. At present even those members of the hierarchy sympathetic to calls for reform (such as the late Cardinal Hume) say they haven't the authority to introduce the necessary changes.

To be more precise, the relaxation of the requirement of celibacy for priests (as in the first millennium) and the ordination of women (as in the deaconesses of the early Church) would not be innovations but a return to earlier traditions. A council would have the authority to do this.

Conservatives might be tempted to go along with this, since reformers (if their proposals were defeated) would have to accept the position or look elsewhere.

Terry Wright

Newcastle upon Tyne

Gay marriage is all about love

Opponents of same-sex marriage, such as Norman Wells (letter, 20 October), all seem to cling to arguments such as "the legal definition of marriage is x" and "the cultural definition of marriage is y". These arguments are nothing more than a cover, conscious or unconscious, for prejudice. Law and culture can be changed, as post-apartheid South Africa has demonstrated.

Anyone who uses the brain that God gave them should be able to discover that two people of the same sex are capable of sharing a love as deep and longlasting as heterosexual people, and should be entitled to exactly the same treatment. It isn't about anatomy, or legal definitions, but about this simple and self-evident reality.

Dr Daniel Emlyn-Jones