India, May 27 -- By Dr. R. Balasubramaniam

There is no moment in modern life more quietly complicated than the one that arrives at the end of a meal, a cab ride or a hotel stay. The service is done. The bill has been presented. And now you must decide how much, if anything, the person who served you deserves as a small acknowledgement of their effort. It is, in theory, a simple act of human generosity. In practice, it is a minor psychological crisis.

Welcome to the world of tipping. Where economics meets ego and arithmetic meets anxiety.

Let us begin with the non-tipper. This is a person of firm principles. They have worked out, usually at some point in their twenties and never revisited since, that tipping is unnecessary, inflationary...