I have an old Joni Mitchell live album called "Miles of Aisles." It's a collection of her work up to 1974, a kind of "Greatest Hits" done live. I haven't listened to it regularly for years, but it's still ingrained in my consciousness. One of the things that sticks in my mind is Mitchell's edgy banter between songs. She seems, at times, downright impatient about singing her old work, the hits her audience had come to hear. Along with her gift for song, Mitchell is also an accomplished painter. At one point in the double album she compares the two disciplines: "You know, a painter does a painting and that's it. He's had the joy of creating it.... No one ever said to Van Gogh, 'Paint another "Starry Night" again, man.'"

I'm sure there was a back story to that comment. No doubt her record label was also telling her, "Hey, Joni, write another 'Chelsea Morning,' as she was struggling to move onto her next muse. Success for a commercial artist often means pressure to repeat that success by trodding the same rutted path. But as a creative artist, once you know the way, you're ready to travel down a different road.

In addition to digging out my old Joni Mitchell recordings, I've been talking with residential architects about the difficulty of making services affordable to a wider range of clients. Apparently the excuse that the American public doesn't appreciate what architects do is getting weaker and weaker. More and more architects are turning away work. Why? Because much of it is bare-bones budget and, from a creative stand-point, somewhat basic. No one wants to paint that painting again.

But think how quickly Van Gogh could have painted a second "Starry Night," and a third, and so on. What the American public loses is the rigor an architect might bring to even that basic house (so much can still go wrong if it falls into unskilled hands). And what the architect loses is the opportunity to hone and perfect a familiar form over time. So all custom homes are prototypes, rough drafts. And they remain expensive, because many of the efficiencies of experience are abandoned for the next new design on the horizon.

Some of the architects I talked with suggested that this drive to take a smooth wheel and hammer it into a square--or something ovoid, perhaps--goes back to architecture school, where invention and difference are prized above all else. Evolutionary invention doesn't earn respect. The result is that architects who like to look back before moving forward are made to feel second rate. They don't do as well in school. Their work doesn't make the pages of professional journals. They don't win design awards. "It's a pretty house, but where's the new idea?" juries say.

What's wrong with the same idea made even better through repetition? Joni Mitchell recorded "Miles of Aisles" about three years after her hit album "Blue," which contained such instant classics as "A Case of You" and "All I Want." Those songs were so much better sung live for the later album, with the complexity and wisdom of three years of artistic development applied to them. For that matter, who wouldn't want to see a later version of "Starry Night" discovered in an attic somewhere?