**80/20 Rule (Efficiency):** Focus on the vital few, ignore the trivial many.
Territory check: Often, there are more opportunities in the under-managed 80% of tasks than in the over-managed 20%.
Signal: We focus excessively on the high-payoff 20% while ignoring the untapped potential in the remaining 80%.
**Inversion (Safety/Reliability):** Avoid stupidity rather than seeking brilliance.
Territory check: Sometimes the downside is already bounded, and the environment is winner-take-most, so “avoid mistakes” caps you at mediocrity while a few bold bets dominate outcomes.
Signal: you’re in this territory: you can survive failure cheaply, but only big upside moves the needle.
**Chesterton’s Fence (Reform/Change):** Don’t destroy what you don’t understand.
Territory check: Some “fences” are pure legacy cruft—kept alive by inertia—whose original function no longer exists, and the cost of keeping them now exceeds the risk of removal.
Signal: nobody can name a current function, only history; the fence creates measurable harm today.
**Hanlon’s Razor (Relationships):** They aren’t evil; they’re just human/clumsy. (Also: impact > intent.)
Territory check: In many conflicts, repeated harmful behavior persists because it benefits the person (status, convenience, or money). Not “evil,” but still strategic—and it won’t change without consequences.
Signal: pattern repeats after clear feedback + low/no cost to them; they benefit from the outcome.
**Parkinson’s Law (Speed/Execution):** Work expands to fill the time available—so use tight timeboxes with explicit scope cuts, not just shorter deadlines.
Territory check: In complex/creative/quality-critical work, compressing time can increase rework, defects, and coordination overhead—making the calendar longer and the product worse.
Signal: high coupling/dependencies, unclear requirements, or quality is hard to test quickly.
**Regret Minimization (Big Life Choices):** Optimize for your 80-year-old self.
Territory check: Your future self’s values can change dramatically, and “max future optionality” can become a rationalization for never committing—so you end up regretting lack of depth, not lack of breadth.
Signal: you keep postponing commitment; you have many open loops but little compounding mastery/relationships.
**Pre-Mortem (Risk Management):** Assume the disaster has already happened, then look for the causes to prevent them now.
Territory check: In high-speed, low-stakes environments, over-analyzing failure modes (analysis paralysis) can kill the "velocity" that was actually your best protection. Sometimes you just need to "ship and fix."
Signal: You are solving for 1% edge cases while the 99% core product hasn't even met the market yet; the cost of the meeting exceeds the cost of a "fast fail."
**Reversibility (Sequencing):** Decide as late as possible for easy-to-change (reversible) choices to maximize fresh info. Decide early for hard-to-unwind (irreversible) choices or those with long wait times. (Also treat compounding choices—health, skills, reputation—as “start early.”)
Territory check: Some “reversible” decisions become sticky through social commitments, sunk costs, or path-dependence—so waiting “because reversible” can quietly make the decision irreversible anyway.
Signal: switching costs grow with time (team habits, identity, contracts, integration debt).
**Base Rates / Reference Class Forecasting (Prediction):** Before your story, ask what typically happens in similar cases.
Territory check: Base rates can mislead when you’re in a genuinely different reference class (new tech, new distribution, rule changes) or when you can materially change the causal drivers that defined the base rate.
Signal: one or more core constraints of the historical set have been removed (cost curve shift, new channel, new regulation).
**Incentives / Principal–Agent (Organizations):** People do what they’re rewarded to do (including unofficial rewards).
Territory check: In many situations, intrinsic motivation, identity, loyalty, or mission dominates incentives—and treating everything as incentive-maximization mispredicts behavior (and can corrode trust).
Signal: people repeatedly sacrifice personal gain for principle, craftsmanship, belonging, or reputation for integrity.
**Goodhart’s Law (Metrics):** When a measure becomes a target, it stops being a good measure.
Territory check: Some metrics remain robust targets when they’re hard to game and tightly coupled to what you actually care about—especially when paired with audits/quality checks.
Signal: the metric has “tamper resistance” (e.g., independent verification, etc.