India, Dec. 26 -- A quarter of a century ago we started forgetting phone numbers. This wasn't necessarily a bad thing; a good memory may be a sign of high cognitive abilities, but intelligence, it is not. As Sherlock Holmes says in A Study in Scarlet: "A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has a difficulty in laying his hands upon it."

The reason we forgot phone numbers was because all the important (and unimportant) ones were in our mobile phones, which, over the past 25 years, have only become smarter. The phone has also become the easiest way to stay connected to the internet...