India, Aug. 8 -- The beauty of romance is that a spark can occur anywhere, with anybody.

Sometimes all it takes is a glance, and two strangers recognise in each other something they have been looking for. "It just clicked," we say. What we mean is that we saw a flash of interest, intelligence, humour, or something else about this person that intrigued us.

It is that recognition, I believe, that explains the flash of excitement we feel about someone we don't know yet. A smile may follow, and a conversation, or more.

Across cultures, races and nationalities, going back centuries, this is often how it has worked. Which is why many of you reading this will know what I mean. (Often, admittedly, we are mistaken; and the spark turns out to be...