Test your actions against the common good

Ask whether what you’re about to do serves or damages the common good — not just your interests.

Why it works

Marcus regularly uses "what serves the rational community?" as a decision-making heuristic, which cuts through self-serving rationalization more effectively than self-interest framing can. Switching the reference point from "what do I want" to "what does the whole need" activates a different reasoning process — less driven by motivated cognition and more by principled evaluation.

How to do it

1. When you face a significant choice, ask: "Does this serve only me, or does it serve those I am part of?"
2. If it conflicts, ask whether the self-serving choice is justified by a principle you would endorse publicly.
3. Let the answer shift the decision or at least the terms of it.

Evidence

Research on moral reasoning and decision-making finds that widening the reference class (thinking about how others are affected) reduces self-serving bias. The common-good standard is the Stoic application of this principle. (mechanistic)

The debiasing effect of considering others is studied; using a Stoic common-good framing as a specific decision heuristic is philosophical practice, not a tested intervention.

Common mistake

Applying the common-good standard selectively — to others’ actions but not one’s own. Sympatheia is a symmetric tool; it applies to everything you do, not just to judging others.