Epistemics & Uncertainty Vocabulary

the alignment between confidence levels and actual accuracy

“Well-calibrated forecasters are right 70% of the time when 70% confident.”

Origin: Arabic qālib (mold); adjusting to a standard

acknowledging the limits of one's own knowledge

“Epistemic humility prevents overconfidence in uncertain domains.”

Origin: Greek episteme (knowledge) + Latin humilis (low, humble)

qualifying statements to acknowledge uncertainty

“Hedging with 'probably' signals appropriate uncertainty.”

Origin: Old English hecg (hedge); to limit risk

producing false information without intent to deceive; filling gaps

“Memory confabulation creates coherent but inaccurate narratives.”

Origin: Latin confabulari (to talk together)

generating plausible but false or unsupported content

“The model hallucinated a citation that doesn't exist.”

Origin: Latin alucinari (to wander in mind)

connecting claims to verifiable sources or evidence

“Grounding responses in documents reduces hallucination.”

Origin: Old English grund (foundation)

the degree of certainty or evidence supporting a claim

“She prefaced her speculation with its epistemic status.”

Origin: Greek episteme (knowledge) + Latin status (state)

a degree of belief in a proposition, often expressed as probability

“His credence in the hypothesis was about 60%.”

Origin: Latin credere (to believe)

measuring and communicating the degree of uncertainty in predictions

“Uncertainty quantification reveals when models are unreliable.”

Origin: Technical term from statistics and ML

things we are aware we don't know

“Planning for known unknowns is easier than for unknown unknowns.”

Origin: Popularized by Donald Rumsfeld (2002)

uncertainty that cannot be quantified with probabilities

“Novel situations involve Knightian uncertainty, not just risk.”

Origin: From economist Frank Knight (1921)

having more certainty than warranted by evidence

“Overconfidence leads to underestimating risks.”

Origin: English over- + Latin confidere (to trust fully)