The coalition government is beginning to unravel. There is no sense of intellectual coherence to the government's programme of the kind that underscored the Thatcherite counter-revolution. There is no commanding intellect or thinker in the cabinet around whom all others can gather and from whom they can learn. There is no text to which we can turn for insight into the Prime Minister's thinking, as we can to Barack Obama's Dreams From My Father or The Audacity of Hope. What does David Cameron believe? What does Nick Clegg stand for? Does the coalition have a post-Blair foreign policy? We have questions but no answers.

The government has many ideas - NHS reform, free schools, the so-called big society, progressive conservatism - but no defining idea that pulls all the threads together. The result is muddle and confusion. U-turns, flip-flops and reversals proliferate. There is an incontinent flow of announcements. Policy is regurgitated, undigested. Decisions are not thought through - the pledge to scrap the School Sport Partnerships, for example, or the proposed sale of state-owned forests. One is reminded of the old Roman adage: Make haste slowly.

Pretty vacant

Yet Cameron thinks he has a big, galvanising idea: the big society. He wishes to enhance the lustre of voluntarism, incentivise activism among the good citizens of our happy land and devolve power from Whitehall to the people. He wants to cut both the supply of, and demand for, the state. But how big can a society be when there is no money to spend?

Randolph Churchill once described the aged William Gladstone, the Gladstone of the Irish Home Rule Bill, as an "old man in a hurry". Cameron is a young(-ish) man in a hurry. He would do well to learn from one of the most successful of all Conservative prime ministers, Robert Cecil, 3rd Marquess of Salisbury, who, when pushed on an initiative or a proposal for change, would say: "Far better not!"

Disparagers of the government like to caricature Cameron and those closest to him as ideologues. They are no such thing. But nor are they philosophical conservatives in the style of Lord Salisbury, whose politics flowed from his pessimism and tragic sense of human nature and gave coherence to his reaction.

This past week, the Prime Minister and his deputy delivered major speeches, the former on the failure of multiculturalism and the need to stop appeasing militant Islam and the latter on economic policy. Both were distinguished by their intellectual vacuity. In his speech, the Prime Minister made no attempt to offer a definition of multiculturalism, which he seemed to conflate with the propagation of radical Islam. To Cameron, does multiculturalism mean more than simply a broad tolerance of difference and respect for minority cultures and traditions? Is it an official doctrine? Or does it mean something more assertive - the establishment of more faith schools funded by the state, for instance, and children increasingly being taught in separate racial and religious communities?

Does Cameron deny the existence of a majority culture - one that is plural, sceptical, liberal, anglophone and Christian in ethos, if not in practice? I presume not. Or does he feel that the majority culture has been subverted by minority cultures - particularly by the ever more assertive culture of political Islam?

The Prime Minister's speech was a good rhetorical performance but no more than that. He offered us a diagnosis of what he thought was rotten in the state of Britain but there was no prescription for renewal and little historical or socio-political contextualisation. Cameron the writer does not have a natural style, as Obama the writer does. Every speech Cameron "writes" reads as if it could have been written by someone else, and that's a problem. He remains a politician in search of an idiom as well as a commanding and persuasive voice. Small wonder his own MPs are so restive.

Book club

It has often been said that we live in an unheroic age, without significant public intellectuals, hence the debasement of our political and cultural discourse. But I don't think that's right. We have no shortage of first-rate public intellectuals, from Amartya Sen and Michael Sandel in the academy to John Gray, Nassim Nicholas Taleb and Rowan Williams outside it. What we are without, certainly in Britain, are politician-intellectuals and politician-writers. There are no thinkers and scholarly essayists in the cabinet comparable to Disraeli, Gladstone, Salisbury or even Tony Crosland. What we have are politician-PRs and politician-policy wonks.

Where are Clegg's and Cameron's - and, indeed, Ed Miliband's - books, novels and learned essays? Where does one look if one wants to read an exposition of the philosophical basis of their ideas or find evidence of the depth of their reading or expressions of their hinterland? All we have are speeches that are invariably the work of not one hand but many.

Disraeli wrote fiction that is an enduring part of the canon of English literature. Winston Churchill won the Nobel Prize in Literature for his writing of history. Gladstone wrote books about the Christian Church and the classical world. Salisbury published long, sceptical, philosophical essays in the Quarterly Review, in which he elaborated his reactionary positions and explored what has been called his "idea-less conservatism".

An idea-less conservatism - would that were so today. Instead, we have a government that has too many ideas and seems addicted to change not as a means but as an end in itself. The zeal of Cameron and Clegg has been denounced from within the cabinet as Maoist. It certainly isn't philosophically conservative or intellectually impressive.

Chaps, far better not!