Much the same, incidentally, is true of the cigars he smokes. He smokes very expensive Havana cigars, of a brand rolled, I am told, in the laps of indescribably beautiful Cuban women.

The tax on these imported luxuries is quite considerable. By contrast, derelicts hanging around Garema Place are smoking roll-your-owns Havana Folly Resurrections, or something similar - the brand popularised by Robert Graves in his immortal Antigua, Penny, Puce.

On these, in their original form, usually as Drum tobacco, a relatively trifling excise was once paid, but the recycled version, from stubs picked up on the street, is tax free. Hence, it is obvious, tobacco taxes are likewise progressive, as are taxes on cattle properties, Bentleys, yachts, and houses in Canberra bought from the proceeds of parliamentary travelling allowances and being a slum landlord for colleagues. You've got to be in it to win.

Mr Hockey, who studied a few economics subjects during his arts-law course, has defensively pointed out that the figures were given to him by Treasury and came from the Australian Bureau of Statistics Household Expenditure Surveys.

He's quite right too - at least about richer people spending rather more on everything, even water - but I'd be fairly certain that no one in Treasury ever told him that this proved that taxes on the things were progressive. That was the deduction drawn by a person who was mostly being a student politician when basic mathematical concepts were being explained at Sydney University.

By all repute, Sloppy Joe was, in any event, not a guy for detail, and, despite the heroic family legends about how his father did well in Australia, Joe himself never did it hard, other than on the footy field. I'd be very surprised indeed if he (or half his colleagues) really understands the difference between single and double differentials - which is what a good deal of Treasury bumph is all about.

But if one can and should sneer, if only from reverse snobbery, it should probably not be from disdain for his lack of ready understanding of the difference between absolute sums and rates. A good many solid citizens, even politicians, share his apparent innumeracy and want of appreciation that a smaller sum, expressed as a fraction of a smaller income, may be a heavier impost than a larger sum as a fraction of a much bigger income.

One should sneer instead at his failure to appreciate that it can be hard to live on an income that is far smaller than his own. Far smaller than the effective income he has always enjoyed or had access to, whether as the son of a publican attending a privileged school, costing more per term than the income of a single mother.

Being a Hooray Henry at a university college, a pretend lawyer while being prepared for an inside rails run in the Liberal Party, then yet another suit on the party payroll. Mostly using his position and time to advance in the Liberal party, than a party organisational man looking for a comfy seat.

Not a guy whose ever had much dirt under his fingernails, or with the personal experience to empathise, other than through an employed speechwriter, with the ordinary decent salt-of-the-earth style of Australian battler said, by his spinners, to encapsulate his outlook on the world.

Nor would I imagine that he has played anything other than the Pitt Street farmer at his tax deductible cattle station near Cairns. A university commentary once doubted he knew a bull from a cow.

The galling thing, and the thing that he simply doesn't get, is that this is a man who can worry greatly at what he claims to be a sense of entitlement by people with a fraction of the access to cash and income he has always assumed as a given.

It is not that he is, and always has been financially comfortable, and with a partner herself able to contribute handsomely to the family's resources and expectations. There are many other politicians like that. But a good many of them do not parade their privilege. And one or two have even seemed to be motivated by an idea that the privilege they have had gives them some sense of moral obligation to help the lives of others, particularly those less well off than themselves.

Joe Hockey is an agreeable enough, self-deprecating enough sort of fellow: but one has never sensed in him any desire to "give back," or to make the lives of ordinary Australians better. He's ambitious enough, and ruthless enough, but for himself and his own, alone.

It is quite true that at various times he has believed in all the fashionable moderate liberal causes, without putting any sort of skin in the game, just as now he has been trying to have himself painted as a hard-line conservative on financial matters.

Like a number of other politicians who were around for quite a while being all things to all people - Andrew Peacock and Brendan Nelson come to mind - it has always been very difficult to work out what he stands for, or whether he really believes in anything at all.

Like them, he is never as unconvincing as when he puts on his severe and stern face. Then you know he is parroting someone else's lines.