If biases are built into how minds work, can anything be done? Yes, though not mainly by trying harder to be objective. The bias blind spot from Level 1 means that knowing about a bias does not reliably protect us from it. The most effective remedies change the procedures we follow and the environments we decide in.

Consider the opposite

In a 1984 study by Charles Lord, Mark Lepper and Elizabeth Preston, people evaluating evidence on a contested question were either told to be fair and unbiased, or asked a specific question: how would you judge this evidence if it had pointed the other way? The second instruction reduced biased evaluation far more than the first. It works because it gives System 2 a concrete task rather than a vague intention. A related habit is asking “What would change my mind?”

Pre-mortems

The psychologist Gary Klein proposed the pre-mortem. Before a project starts, the team imagines that it is a year later and the plan has failed, then lists the reasons why. Treating failure as a fact to explain makes it easier to voice doubts people would otherwise keep quiet. It targets overconfidence, the planning fallacy and the pressure to conform.

Checklists

Aviation adopted checklists after a 1935 test flight crash of a new Boeing bomber, blamed on an experienced crew forgetting a simple step. Checklists catch errors of memory and attention that expertise does not prevent. In a 2009 study of a World Health Organization surgical safety checklist across eight hospitals in different countries, deaths and major complications both fell: deaths from about 1.5 percent to 0.8 percent of patients, and major complications from about 11 percent to 7 percent.

The outside view

Kahneman distinguished the inside view, which focuses on the details of your own case, from the outside view, which means comparing your plan with the record of similar past projects, sometimes called a reference class. Kahneman told of a team, including himself, writing a school curriculum. The members guessed they needed about two years. When asked, an experienced member admitted that similar teams had often failed to finish at all, and that none he knew had finished in less than about seven years. The project took eight. The outside view is the best single remedy for the planning fallacy.

Slowing down, when it matters

System 2 is costly, so it cannot check everything. Save deliberate thinking for decisions that are important, unfamiliar or hard to reverse. Sleep on big decisions, write out your reasoning, and treat strong emotion or urgency as signals to pause.

Structured decisions

Groups can design out many biases:

• Set criteria in advance, before seeing the options, so that a favored option cannot reshape the standards.
• Score options separately on each criterion, which limits halo effects.
• Gather independent judgments before discussion, by having people write down estimates first, to avoid anchoring on the first speaker and conformity to the group.
• Use structured interviews, asking every candidate the same job-related questions. Reviews of the research find they predict job performance better than casual, unstructured conversations.

Intellectual humility

Underneath all of these tools lies a disposition. Intellectual humility means recognizing that your beliefs might be wrong and staying open to revising them. The political scientist Philip Tetlock found that the most accurate forecasters in his long-running tournaments tended to update their views in small steps as evidence arrived, kept score of their own predictions, and treated beliefs as hypotheses to test.

Biases are part of being human, but so is the ability to build habits and institutions that catch them.

Worked example: a pre-mortem for a community garden

A neighborhood group plans to turn an empty lot into a community garden, and expects it to be thriving in three years. Here is how this level's tools could improve the plan.

The outside view. One member asks a regional gardening network about similar projects. Of 10 community gardens started in the area in recent years, 4 were still active after three years. That is 40 percent. The group's plan is not doomed, but the base rate says success is far from automatic.

The pre-mortem. Each member silently writes answers to this prompt: “It is three years from now and the garden has failed. Why?” Common answers include: no reliable water supply; a few volunteers did all the work and burned out; no agreement with the landowner beyond one year; plots left unused while others waited.

Checklists. The group turns the pre-mortem into a startup checklist: written land agreement, water access confirmed, rota of at least ten volunteers, rules for unused plots, and a simple budget.

Independent judgments. To choose between two possible layouts, members score each layout on agreed criteria (cost, accessibility, sunlight, ease of watering) before discussing them. The most confident speaker cannot anchor everyone else.

Consider the opposite. The organizer who loves layout A asks, “If someone showed me this evidence favoring layout B, would I find it convincing?”

Humility and review. The group writes down its predictions for the first year, such as the number of active plots, and agrees to compare them with what actually happens. Keeping score turns hopes into testable forecasts.