Truth vs. Usefulness

I love this essay "The Truth Wears Off" by Jonah Lehrer published by New Yorker.

People often equate truth with usefulness, perhaps because we are in America. If we take the view of William James' Pragmatic theory of truth, then perhaps usefulness is the truth.

We often apply ideas we commonly agree as useful, but we do not know for certain what the reason is. For example, "we feel better and are more energized when we spend time outdoors." Is this truth or merely usefulness?

"The truth of an idea is not a permanent property and it does not lie in it. The truth happens to an idea" (William James).

We are in an era of ideas (truths) overload. Some ideas are very true to some people (such as Seth Roberts "Effect of One-Legged Standing on Sleep"), but may seem ridiculous to others. I do not doubt that Seth Roberts one legged standing works for him to achieve better sleep, but many other methods may work just as well.

Focus was important for productivity in the past. It is perhaps essential today, otherwise we will all get lost in the piles of "truths" google search provide us.