All of this did become particularly clear to me when, recently, I went to Mexico to see the work of the great Mexican architect Luis Barragán, who died about 10 years ago. Color was his main theme, and not timid color, but the most vivid kind. Large yellow, pink, blue whitewashed walls, rich in surprising textures. I visited a chapel built in the 1950's for some cloistered nuns, and I don't remember seeing any other example of modern religious architecture that moved me so. Only the interior is interesting; from the outside it is just like the other houses around. In this interior symmetry is eschewed, like in the great medieval churches. Look, on the other hand, for anything that's not symmetric in the great cathedrals in the U.S. As one sits in Barragán's chapel, the light of the sun, filtered through painted glass, reflected on bare, colored walls, slowly changes the view and the shadows of the spare cross, altar and furniture. On the Web I found the speech Barragán gave in Washington, DC in 1980; it is in Spanish; I don't know if you can find an English version on the Web. In this speech, the Mexican architect does not speak of geometry or topology, as most American architects do, but of myth, beauty and joy. The key words of his art, he says, are serenity, silence, mystery, surprise and the Spanish word "embrujo," which is hard to translate, but "bewitchment" comes close. In the end, the aim of architecture is to make human life fuller, more beautiful, easier, and to help us avoid hopelessness. For in the vast, stellar expanses of space and in abstract, infinite time (whether the latter be a straight line or a circle), there is no hope for us.