Master Decisions
The mental models that separate good calls from regret — opportunity cost, expected value, second-order thinking.
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Start learning →Opportunity cost
Understand opportunity cost — the real price of every choice is the next-best alternative, and why ignoring it leads to bad decisions.
Sunk cost fallacy
Spot the sunk cost fallacy — past spending shouldn't drive future choices, but emotionally it almost always does.
Expected value
Use expected value to reason under uncertainty — multiply outcomes by probabilities, and judge decisions on process not results.
Whether to quit my job
Decide whether to quit your job — separate fixable from unfixable, weigh real alternatives, and reduce regret rather than chasing certainty.
Moving cities
Decide whether to move cities — weigh career, relationships, cost of living, and identity against the friction of starting over.
Pre-mortems
Run a pre-mortem — imagine the project failed and ask why, surface risks early, and turn pessimism into a planning tool.
Analysis paralysis
Break analysis paralysis — set a decision deadline, lower the stakes of reversible calls, and trade certainty for speed when it doesn't matter.
Second-order thinking
Apply second-order thinking — ask what happens after the first consequence, and avoid 'solutions' that create worse problems downstream.
Gut vs data
Choose between gut and data — when intuition is encoded expertise, when it's just bias, and how to combine both honestly.
Reversible decisions
Distinguish reversible from irreversible decisions — move fast on the first, slow on the second, and stop treating them the same.