Three recent conversations:
1. While in a bookstore perusing the bicycling magazines at length (with only the vaguest intention to buy), a disheveled man beside me starts making loud pronouncements on the nature of time, triggered by the cover art on a popular science magazine. He catches my eye, and partly out of my British obligation to "good manners" and partly because I'll talk with anyone who has an opinion about science, we engage in a shouted exchange about how time is measured, and just how off-base science is, according to him. Fairly interesting, I think, but we effectively clear the magazine section of other browsers.
2. At lunch, a three-way conversation with colleagues becomes far too serious as we discuss the merits of science versus other value systems, such as religions or philosophies. Of course, one of us is playing devil's advocate, forcing the other two to debate that ...
