Critic and artist Cordelia Oliver often recalled her years as a student at Glasgow School of Art during the Second World War.

To make pocket money Oliver was one of a team of firewatchers whose duty was "to sleep in the school and keep an ear cocked for the air-raid siren". She remembered the director, William Hutchison, drily telling them: "If we painted in large letters 'Glasgow School of Art built by Charles Rennie Mackintosh' on the roof no self-respecting Luftwaffe pilot would ever think of bombing us."

Nor did they, fortunately. In those days there were no such things as fire doors or fire regulations and students were able to rove through the corridors unchecked. That this magnificent building has been brought low in an age of rigorous health and safety checks is only one of the terrible ironies of its near destruction.

The sight of flames leaping from its roof last Friday was sickening. You don't need to have been a student there to feel as if a personal blow has been inflicted by its ruin. Anyone who has set foot in Mackintosh's masterpiece will have felt anguish. That the exquisite library, the jewel in this building's crown, has been reduced to cinders, is little short of tragic. I've visited a few of Mackintosh's delightful houses, but none has the elegance, grandeur and practical chutzpah of the art school.

As former student Alison Watt said: "To this day, I have never painted in a studio that bettered the one I worked in at Glasgow School of Art ... Mackintosh understood what an artist needs. A place in which to think and in which to imagine."

Much has been said about the inspirational qualities of Mackintosh's building. The brilliance of its construction helped elevate the minds and nurture the talent of students who worked within its walls. Though thousands of artists have passed through its doors, spattering and begriming it, treating it with familiarity and disrespect as well as awe, until last week it had survived a century almost unscathed, like a medieval castle on which swords, battering rams and cannon balls could make no mark.

Is there another building like it in Scotland? I can't think of one, intended for public use, that even comes close. Modern schools, hospitals and airports, housing estates and shopping centres are usually unspeakably bland and dull. You'd find more inspiration in a bus shelter. Some architects' vision seems inimical to creative thought or happiness, their use of harsh lines, cheerless materials and characterless uniformity suggesting those who enter are mere drones in a business that can spit them out whenever it likes.

Even Enrico Miralles's parliament, while in many ways admirable, cannot begin to compete with Mackintosh's originality and the effortless harmony he created between beauty and functionality. And yet Scotland has been home to many great architects, from the likes of William Adam and his sons Robert and James, to William Henry Playfair and David Bryce. The country should be replete with gems.

As a nation, however, we have been singularly poor at appreciating the importance of aesthetics in day-to-day life. The drabness of countless high streets is testimony to the belief that, so long as a place is wind and water tight, it has served its purpose. Yet as Richard Murphy Architects, who designed the first Maggie's Centre, were well aware, a building is far more than bricks and harling. It is a space for living, as well as one can. An attractive, well-constructed, practical house, workplace or clinic can make a marked difference to productivity and wellbeing.

No-one was more aware of that than Charles Rennie Mackintosh. I remember being impressed when shown the futuristic cylindrical shower in the art school director's office and wishing it was mine. Even to think of including a private shower was ahead of its time.

Those mourning the school's dreadful fate might take comfort in knowing that Mackintosh's meticulous plans for the building can, and surely will, be brought back to life.

When that happens, it will prove that the most important thing about the Glasgow School of Art is not its venerable age or distinguished history, but the sheer genius of its design.