Though his official biographer tends to deny it, there is a very noticeable gap between Lucian Freud's present style and the way he painted at the outset of his phenomenal career.

This, of course, might be expected. There would surely be something wrong with a painter who painted in the same way in his eighties as he did in his teens. The curious thing about Freud is that the change was extreme and instantaneous. It took place in the mid-1950s — in terms of the great 1987 retrospective, which established Freud as a major figure in world art, somewhere between Hotel Bedroom in 1954 and A Young Painter in 1957.

Nowadays everybody knows something about Lucian Freud — record prices at auction, especially when they ascend into the millions, will always do that for an artist. But, almost inevitably, it was the works that fetched the giant prices by which Freud would be popularly identified. And these were all from his more recent period, in his highly distinctive later style. This is extravagantly what they call “painterly” — lashings of paint, applied to the canvas with sweeping panache, and based on a lot of confident draughtsmanship.

The draughtsmanship needs to be confident, because otherwise one might doubt the reliability of the likenesses in his human figures, which tend to favour the grotesque if not the positively ugly. This slightly unusual taste — certainly in a British artist — was no doubt always part of his make-up.

When he was called upon to compile one of the National Gallery's Painter's Eye selections from the permanent collection the result was quite mysterious — until one realised that every single piece contained something undeniably ugly.

The same quirk of taste can be seen frequently in his earlier work. This was if anything even more distinctive than his later work, arrived at when he was still in his mid-teens (the portrait of Stephen Spender was painted when Freud was 17). It sometimes verged on the childlike, without ever being childish. It was defined by crisp lines, and the paint was applied very lightly and thinly — almost as an illustrator might.

It must be said that, even then, Freud was seldom very flattering to his subjects. His passion for exactness often amounted to ruthlessness.

But all the same, prominent people, with whom he came into contact very readily from a young age (unsurprisingly given his family background and educational history), seemed to recognise that he and his talent were exceptional, and did not mind too much if he portrayed them in a less than flattering light. All of these rediscovered paintings date from these early years, and as yet none of them seems likely to arrive on the auctioneer's block very soon.

But if they ever do it will be interesting to see whether those who prefer the earlier style to the later (and they are many) will be able to put their money where their mouth is and equal the millions that the later works achieve.

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