To restore or not to restore? One would be hard-pressed to gaze upon the fabulous restored Tintoretto at Kingston Lacy and conclude that it would have been better left as the dingy canvas that William Bankes brought to Britain 160 years ago.
But the fact is that not all artistic restoration jobs are so unambiguously beneficial. When Leonardo Da Vinci's Last Supper in Milan was restored there were some areas of the fresco that were beyond repair. The restorers decided to re-paint these parts in subdued watercolours to indicate they were not original work. The effect was not what Leonardo intended.
And if restoration is desirable, why stop at paintings? Why not rebuild the Parthenon? Or the Colloseum? The answer is that we see nobility and pathos in ruins and we recognise that a building's decrepitude tells us something about its history. But is there not nobility and pathos in a faded old master too? And doesn't a painting's damage also tell us something important about its history? After all, Vasari declared the Last Supper already "ruined" when he was writing his Lives. And that was in the 1550s. We gain something when we restore. But we need to be mindful of what we sometimes lose too.