This article is an excerpt from the Shortform book guide to "Algorithms to Live By" by Brian Christian and Tom Griffiths. Shortform has the world's best summaries and analyses of books you should be reading.

How do you make an informed decision when there are just too many variables to consider? What about variables that are yet unknown?

Whenever you make a decision, you’re using all the existing data of your life so far to predict what choice will result in the best outcome. But as statistics tell us, taking too many variables into account results in faulty predictions. That’s why, sometimes, the best way to make a complex decision is to make a less informed decision.

Here is why you should make less informed decisions.

## To Make Better Decisions, Consider Less Information

When you are faced with a decision that involves too many variables, you may be better off making a less informed decision. Base your decisions on only the most relevant facts and ignore everything else to avoid jumping to unfounded conclusions. In their book Algorithms to Live By, Christian and Griffiths propose several solutions for making complex decisions:

### Rule #1: Choose the Simplest Solution Unless You Can Justify Complexity

Christian and Griffiths support their argument by citing Occam’s razor—a well-known principle stating that the simplest hypotheses are most likely to be true and the simplest solutions are often the best. They argue that this principle should be a key influence on your decision-making strategy: Cast more doubt on decisions that require a complex explanation to justify them.

For example, if your son gets bad grades, but you suspect that all his teachers are conspiring to keep him back a grade and want to make a complaint to the school board, you’re probably overfitting. You’re attributing too much significance to the wrong evidence: the personalities of his teachers. The simpler explanation—that your son isn’t studying very hard—is more likely to be true.

#### When You Can Use Complex Solutions

Christian and Griffiths make it clear: This isn’t to say that you should never embrace complex solutions, just that you should seek out more supporting evidence before committing to them. With this in mind, they argue that the most reliable form of evidence is found through a process called “cross-validation.”

The authors explain that in statistics and machine learning, cross-validation is the practice of testing a model’s predictive power. By creating a model from a set of data and then making sure it can accurately predict data points it hasn’t seen yet, you can verify that it accurately interpreted the first set of data.

### Rule #2: When in Doubt, Decide Sooner

One strategy that Christian and Griffiths offer to combat indecision is to make your decisions sooner rather than later. This prevents you from overthinking and adding complexity that is likely to mislead you. More often than not, the first factors we consider when making a decision are the ones that will have the greatest impact on the outcome.

Imagine someone you know well asks you on a date. If your first instinct is to say no, that’s probably the right call. In those first few seconds, you only have time to evaluate the most important factors—for instance, whether or not you’re attracted to and respect them. Given time, you could likely rationalize saying yes by considering less important details like their income level or how polite they are, but you would be falling victim to overfitting.

Simple Rules for Making Complex Decisions

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#### Like what you just read? Read the rest of the world's best book summary and analysis of Brian Christian and Tom Griffiths's "Algorithms to Live By" at Shortform .

Here's what you'll find in our full Algorithms to Live By summary :

• How to schedule your to-do list like a computer
• Why making random decisions is sometimes the smartest thing to do
• Why you should reject the first 37% of positions in your job search

#### Darya Sinusoid

Darya’s love for reading started with fantasy novels (The LOTR trilogy is still her all-time-favorite). Growing up, however, she found herself transitioning to non-fiction, psychological, and self-help books. She has a degree in Psychology and a deep passion for the subject. She likes reading research-informed books that distill the workings of the human brain/mind/consciousness and thinking of ways to apply the insights to her own life. Some of her favorites include Thinking, Fast and Slow, How We Decide, and The Wisdom of the Enneagram.