Establish a closing ritual. Know when to stop working. Try to end each work day the same way, too. Straighten up your desk. Back up your computer. Make a list of what you need to do tomorrow.

A general “law of least effort” applies to cognitive as well as physical exertion. The law asserts that if there are several ways of achieving the same goal, people will eventually gravitate to the least demanding course of action. In the economy of action, effort is a cost, and the acquisition of skill is driven by the balance of benefits and costs. Laziness is built deep into our nature.

People have little idea, by and large, of the investment world. They are convinced they have an advantage.

One study found that people who just thought about watching their favorite movie actually raised their endorphin levels by 27 percent.

The illusion that we understand the past fosters overconfidence in our ability to predict the future.

Finally, the illusions of validity and skill are supported by a powerful professional culture. We know that people can maintain an unshakeable faith in any proposition, however absurd, when they are sustained by a community of like-minded believers. Given the professional culture of the financial community, it is not surprising that large numbers of individuals in that world believe themselves to be among the chosen few who can do what they believe others cannot.

The idea that the future is unpredictable is undermined every day by the ease with which the past is explained.