Anti-Thesis

The written list of categories an investor has decided in advance not to invest in, each with the reason and an explicit exception clause.

Example

"Early-stage biotech - I cannot evaluate a clinical claim and the outcome turns on one. Exception: a qualified scientific partner does the technical work and co-invests."

Important

Its value comes entirely from being written before any specific opportunity is live. An exception invented in the moment is a rationalisation, and it is indistinguishable from a real condition from the inside.

Related terms

• Investment thesis — A written statement of what you believe about an investment, at what price it is worth owning, and what specific observation would tell you that you were wrong.
• Circle of competence — The set of businesses, assets or markets you understand well enough to judge what they are worth and what could realistically go wrong with them.
• Pre-Commitment — Deciding a rule in advance, at a moment when nothing is at stake, in order to bind the version of yourself that will face the decision under pressure.

Lessons that explain it

• A process you actually run beats a better one you do not — Screening only compounds if it is written down, identical every time, and produces a record - which is what turns a year of declined opportunities into knowledge about a category. (11 min)
• The list of things you have decided not to do — An anti-thesis is written in advance and costs nothing to write, which is exactly why it works when the attractive version of the thing you swore off finally shows up. (9 min)
• The first forty minutes decide the next forty hours — A thesis is only worth writing if it changes what you do at intake. This is the mechanics of applying it fast enough to protect the time it was meant to protect. (13 min)

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