THE IDEA
Smart enough, not smart enough for everything
Classical economics assumed people are rational: they have perfect information, unlimited processing power, and clear preferences. They weigh every option, calculate the optimal choice, and act accordingly. Herbert Simon pointed out that this describes no human who has ever lived.
Real people have limited information - they don’t know everything relevant to the decision. They have limited processing capacity - they can’t analyse every option. They have limited time - decisions need to be made before the full picture is available. And they have limited attention - they’re making this decision while also making dozens of others.
Bounded rationality isn’t a flaw. It’s a description. People are rational - they make sensible decisions given their constraints. But “given their constraints” is doing enormous work. A manager who makes a poor strategic decision isn’t stupid. They’re working with incomplete information, under time pressure, with cognitive resources depleted by everything else they’ve dealt with that day. The decision was rational within their bounds. The bounds were too narrow for the decision they faced.
IN PRACTICE
Rational within the limits
A doctor sees 30 patients a day. For each, they need to listen, diagnose, consider interactions with existing medications, weigh treatment options, and explain the plan - in ten minutes. The doctor is intelligent and well-trained. But bounded rationality means that by patient 25, the cognitive resources for careful deliberation are depleted. Heuristics take over. Shortcuts are used. Most of the time, they work. Occasionally, they produce an error that careful analysis would have caught. The error isn’t incompetence. It’s the inevitable consequence of a bounded system operating beyond its optimal load.
A shopper faces 47 varieties of jam. Classical rationality says: evaluate each one and choose the best. Bounded rationality says: the cognitive cost of evaluating 47 options exceeds the benefit of the optimal choice. The shopper picks the familiar brand, or the one on sale, or the one at eye level. Not optimal. Rational given the bounds.
A policy team designs a regulation. They consider the immediate effects, the stakeholders they know about, and the scenarios they can model. They don’t consider the third-order effects, the stakeholders who aren’t represented, or the scenarios that nobody in the room has imagined. The policy is reasonable given what they knew and could process. The unintended consequences come from the gap between their bounded analysis and the unbounded complexity of the system they’re regulating.
WORKING WITH THIS
Designing for bounded humans
Accept that bounded rationality is the starting condition, not an error to be corrected. Then design systems, processes, and environments that work within human bounds rather than assuming them away.
Reduce the number of decisions people need to make. Provide defaults. Simplify choices. Eliminate unnecessary options. Every decision that can be automated or removed is one less drain on bounded cognitive resources.
Improve the quality of information available at the moment of decision. Not more information - better information. The right data, in the right format, at the right time. Dashboards that highlight what’s changed. Summaries that surface what matters. Alerts that flag what needs attention. Design the information environment for bounded humans, not for ideal rational agents.
THE INSIGHT
The line to remember
People don’t make irrational decisions. They make rational decisions within bounds that are almost always narrower than the situation requires.
RECOGNITION
When this is in play
You’re seeing bounded rationality when a smart person makes a poor decision and the explanation is obvious in hindsight. When decisions degrade in quality later in the day, later in the meeting, or later in the process. When people default to familiar options rather than exploring better ones. When someone says “how could they not see that?” - the answer is usually that their bounds didn’t include it.