The voice of reason? (Image: Katherine Streeter

You think more words than you speak – perhaps because language really does shape the way we navigate the world

THERE I go again, talking to myself. Wherever I am, and whatever I’m doing, words bounce around my head in an incessant chatter. I am not alone in my internal babbling. Measuring the contents of people’s minds is difficult, but it seems that up to 80 per cent of our mental experiences are verbal. Indeed, the extent of our interior monologue may vastly exceed the number of words we speak out loud. “On average, 70 per cent of our total verbal experience is in our head,” estimates Lera Boroditsky of Stanford University in California. The sheer volume of unspoken words would suggest that language is more than just a tool for communicating with others. But what else could it be for?

One answer to that question is emerging: language helps us to think and perceive the world. Boroditsky and other researchers are finding that words bring a smorgasbord of benefits to human cognition, from abstract thinking to sensory perception. These effects may even explain why language evolved in the first place.

The idea that language guides human thinking and shapes perception has a long and turbulent history. Philosophers have toyed with it for centuries, but its reputation became tarnished before modern psychologists could begin putting flesh on its bones.

This fall from grace can be traced to the demise of a controversial hypothesis known as “linguistic relativity”, put forward in the first half of the last century by Edward Sapir at Yale University and …