Stumbling on Happiness

Introduction: The Human Ability to Look Forward

Humans are the only animals that consciously think about the future. While many animals act in ways that seem like they are planning for what is to come, their behavior is usually a programmed response to immediate triggers. For instance, a squirrel burying a nut in the autumn is not contemplating the cold months ahead or worrying about a food shortage. Instead, its brain is simply reacting to the decreasing amount of sunlight, which triggers an automatic burying instinct. The squirrel understands the future in the same way a falling rock understands gravity, acting as a passenger to the laws of nature rather than a conscious planner.

The human brain operates as an anticipation machine, and its greatest achievement is the ability to imagine objects and episodes that do not exist in reality. This is different from the automatic, nonconscious way that brains predict what will happen in the very next second. When you read a sentence, your brain is constantly guessing the next word based on the ones that came before it. If a sentence ends with a word that makes no sense, you feel a sudden burst of surprise. This surprise is the brain’s way of signaling that its immediate prediction was wrong. Even sea slugs and human infants perform this kind of immediate prediction, but only adult humans can look past the next few seconds to imagine events years down the line.

This unique ability to think about the distant future is tied to the frontal lobe, a part of the brain that sits right behind the forehead. In the long history of evolution, the human brain experienced a sudden growth spurt that more than doubled its mass, and a huge portion of that growth was dedicated to the frontal lobe. For a long time, doctors did not realize how important this area was because people could survive and seem relatively normal even if it was damaged. A famous example is Phineas Gage, a railroad worker who had an iron rod blown through his skull in the nineteenth century. He survived and could still speak and work, but his personality changed, and he completely lost his capacity for future planning.

Modern science has shown that the frontal lobe is the critical piece of machinery that allows us to project ourselves into time. People with damage to this area often become trapped in a permanent present state. Researchers studied a patient who, after a severe head injury, could describe what a future was in a technical sense but could not imagine himself existing in it. When asked what he would be doing the next day, his mind went entirely blank. Without a functioning frontal lobe, the concept of tomorrow simply disappears, leaving a person locked into their immediate space and time.