Substitution

When faced with a hard question, System 1 often answers an easier, related one instead, without noticing the swap, and maps that answer onto the hard question.

Why it Matters

Substitution is the engine behind most heuristics and biases: difficult judgments about probability, value, or the future get silently replaced by easy impressions of similarity, ease of recall, or current feeling. It explains why confident answers can be systematically off target.

Signals

• A fast answer to a genuinely hard question.
• The question you actually feel differs from the one that was asked.
• Judgment tracking an easy attribute rather than the relevant one.

Benefits

Spotting the substitution names the bias and points back to the real question that should be answered.

Risks

Mistaking the easy answer for an answer to the actual question; never noticing the swap occurred at all.

Tensions

Substitution makes fast functioning possible, but the very convenience that makes it useful is what produces the error.

Examples

Judging "how likely is this project to succeed?" by "how good does the plan feel?"; answering "how happy am I with my life?" with "what is my mood right now?".