1. the generality originally proposed in 1867 by Hermann von Helmholtz that an observer will tend to perceive the most likely interpretation of a visual stimulus (i.e., the one with the highest probability of being correct). This is in contrast to the simplicity principle, elaborated in 1953 by U.S. psychologist Julian E. Hochberg (1923–  ) with Edward McAlister, which states that an observer will tend to perceive the simplest interpretation (i.e., the one with the shortest description).

2. a foundational tenet of statistical inference stating that where there is an unknown population parameter, θ, and an observed sample distribution, x, all relevant information about the population distribution is contained in the likelihood function for x.