These days, a building's quality is defined by whether it works as an advertisement for itself – a fact brought home by one wilful masterpiece that doesn't
I don't know how I'd managed to miss it. All these years of ambling about London, gaping, trying to loose myself in what Borges called "Browning's red brick labyrinth", hoping against hope that around the next corner there would be something to incite the frisson that only buildings can … It's going on half a century since I first set eyes on St Paul's yet my memory of it then – black, and surrounded by pitted bomb-sites – is so powerful that it still supplants the actuality of today's comparatively clean cathedral.

Evidently, the longer one spends exploring (or malingering), the frailer the chance of making the sort of discovery that can match St Paul's or St Pancras or Cliff Road Studios or the Chinese garage at Beckenham or the Los Angeleno bungalows near the Welsh Harp. Yet one doesn't stop yearning: London does incite a faith in serendipity.

I'd certainly been to Guildhall before, but Dance's stage set of a facade never really held much appeal for me – symmetrical Georgian gothic is a shameful blind spot of mine – and although I often glimpse it from Cheapside, I am not drawn to it. Hence my ignorance of its neighbour. Not St Lawrence Jewry, but the range to its west – the Guildhall library, offices and architectural bookshop – that I saw while walking down Gresham Street the other day. "Whatever is this?" I wondered.

Whatever it is, it's the real thing. Energetic, mannered, jagged, bloody-minded, strenuously original and of the 1960s at their most abundantly confident. I was excited, delighted. Pale bronze windows, quirky cantilevering, an absence of right angles, an insistent, restless yet controlled rhythm, a bizarre canopy and an even more bizarre – almost freestanding – pod whose geometry is sui generis. This is a work of high-octane architecture. It came as no surprise to discover that it was by Richard Gilbert Scott, who might be described as a dynastic architect and whose Catholic churches in the West Midlands are similarly inspired, if on a smaller scale. Similarly perverse, you might say; indeed would say if you find this stuff too noisy, too clamouring for attention.

All professions love prizes. But to dispense one gong for every third submission seems reckless

Scott's buildings are quite bereft of modesty; they refuse to dissemble their artifice, they are exhibitionistic, forever up to their party tricks: but they are, nonetheless, untainted by populist accessibility. We do not make their like nowadays. That truism is brought wearisomely home by this year's Civic Trust awards. I know the judges can only select from what has been submitted, but the gongs presumably reflect some multidisciplinary consensus about what is best in urban schemes.

All professions and industries love prizes. But to dispense 185 of them – that's one gong for every third submission – seems recklessly generous. What largesse! What – dare one say – indiscriminate lessening of an award's value … But then, just as every doctor is "eminent" and every politician "most capable", so is every architect "award winning". These quasi-official pats on the back surely do no harm. But the question should be: do they do any good? Do they incite improvements? Or do they foster a flock mentality, a uniformity?

Like the Civic Trust's eminent and most capable national panel of judges I know most of the buildings from photographs. Fine: a building's appearance is hugely important. But it's far from the sole criterion of its excellence. I have sat on such panels, and one pretty soon realises that what is being assessed is a building's mediation by a photographer that, while it may not be mendacious, is never neutral.