Avoid Ruin Above All

April 13, 2021

In any repeated game, the single most important rule is: do not get eliminated. Performance is subordinate to survival, because irreversible losses absorb all future gains.

"Irreversibility absorbs future gains. This means that you cannot extrapolate future outcomes from solely the expected outcomes of the activity performed once." Nassim Nicholas Taleb

The Russian Roulette thought experiment makes this visceral. A single round has a positive expected value of $5,000. But play a hundred rounds and the expected outcome is $0 you are almost certainly dead. The expected value per round does not change, yet the lifetime outcome collapses to nothing. This is the core lesson of non-ergodicity: what works on average across a population can destroy any individual member over time.

This principle extends far beyond gambling. In investing, losing your capital means losing not just the money but every future return it could have generated. In careers, a burnout or reputational catastrophe can nullify years of accumulated advantage. In relationships, a single betrayal can permanently close the door to rebuilding trust. The common thread is irreversibility once you cross certain thresholds, there is no recovery.

Anthony Deden built his entire investment philosophy around this idea. For him, "risk was the idea of losing your capital permanently with no ability to ever recover it." His single investment policy became protecting, enhancing, and deploying capital permanently. Not maximizing returns. Surviving.

The practical implication is not to avoid all risk that introduces its own dangers of stagnation and obsolescence. The goal is to distinguish between calculated risks whose consequences you can recover from and reckless exposures whose consequences might permanently debilitate you. Maximize growth that conserves survival.

Takeaway: Never accept a bet, however attractive the expected value, if losing means you cannot play again.

Avoid Ruin Above All

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