Ten years ago, a philosophy professor at Princeton wrote a book with a provocative, slightly indecent title. It was a surprise bestseller, reaching number one on the New York Times’s list, and university book shops in America still do a roaring trade in copies of Harry Frankfurt’s On Bullshit, along with the usual Vonnegut and Sartre. In 2014, something similar happened when Thomas Piketty’s Capital in the 21st Century sold 1.5 million copies in English, French, German, Mandarin, Urdu, Norwegian, Choctaw and so on.

Not to be outdone, Princeton University Press has enlisted Frankfurt to produce a response to Piketty. On Inequality comprises two journal articles, ‘Equality as a Moral Ideal’ and ‘Equality and Respect’, the former first published nearly three decades ago, plus a 200-word preface that mentions Piketty, an acknowledgements page and some notes. The texts of the articles are very slightly altered.

In the first section Frankfurt argues that inequality of wealth is not inherently immoral. We have a duty, he says, to ensure that no one goes without life’s necessities, a duty that does not entail my earning the same as Taylor Swift. You would, I think, be hard pressed to find someone who disagrees with this. Virtually no one in the United States or Europe today is calling for guillotine-enforced uniformity of wages or salaries across the board, nor would the most recalcitrant Tea Partier or Thatcherite fail to concede that a man who loses his legs while dutifully engaged in the rational pursuit of his self-interest has earned the right to a bit of help. Engels himself referred to ‘the elimination of all social and political inequality’ as ‘a most dubious expression’.

When I say that Frankfurt ‘argues’, though, what I really mean is that he asserts this not very controversial point over and over again, with increasing stylistic flatulence. This book is almost entirely bereft of analogies, illustrations or examples, whether anecdotal or statistical. The only ones that I recall involve food: the excesses of the very rich are compared to ‘the gluttony of those who gobble down considerably more food than they need for either nutritional well-being or a satisfying level of gastronomic enjoyment’. Are there other kinds of gluttony?

Occasionally Frankfurt does get sidetracked. Absent from the version of chapter one published in Ethics is the contention made here that redistributing wealth leads inevitably to inflation: if we give the hard-up more money, they will become greedy and prices will soar. Supply of goods, in this view, is more or less fixed. This is certainly a novel argument, at odds with the well-known alternately accepted theories propounded by Lord Keynes and Milton Friedman. By way of explanation, Frankfurt tells us that: ‘This relationship between redistribution and inflation has been explained to me (in correspondence) by Professor Richard Robb of Columbia University’s Department of Economics.’

Right then. In part two, Frankfurt makes an interesting argument about the nature of respect. He distinguishes between treating people equally, which in his view is not morally necessary, and treating them with respect, which is. By ‘respect’ he means due regard for people in light of their particular qualities, and so on, though he acknowledges that some of these qualities are universal: the need for food, shelter and so on. We all deserve to have enough to eat and to have roofs over heads; we do not all deserve to be treated with solemn pomp.

This book baffled me. I tried for hours to see how ‘satisfied with his current level of satisfaction’, a key phrase from part one, could be interpreted as anything other than a tautology, and I could not figure out what Frankfurt’s copious economically illiterate references to marginal utility had to with the price of tea in China. At one point he assures us that, despite his philosophical claims, he himself supports the taking of certain redistributionary measures ‘to eliminate or alleviate’ income inequality. Which ones? Why? Were his editors not curious?

If it had been expanded and substantially reworked, it might have been a trade title worth selling inexpensively; had it included more of Frankfurt’s uncollected papers, it might have been a nice addition to some monograph line or other. But who, I wonder, is the intended audience for the book in its present form? Stalinists of the broad-minded, forbearing variety? People without access to public libraries and printers? The publicity packet says that the book presents a ‘serious challenge to cherished beliefs on both the political left and right’, which is true enough, I suppose, if the spectrum runs from Lin Bao to Grandfather Smallweed with nothing in between.

I should add that On Inequality has been printed in a clear, attractive typeface on paper of the highest quality.