Archives par étiquette : falsifiability ; falsification

Karl Popper on falsification of probabilistic statements

If in ten throws [of a die] I obtain « 1 » six times, then I will conjecture that something is wrong with the probability prediction [P(1) = 1/6]; if, say, in the very next five throws I get « 1 » two of three times again, I will be convinced that the prediction (for this case), and with its specific assumptions, are falsified: I will try to change the assumptions. Initially, I will not change the natural laws but assume that certain other assumptions were false. Above all, I will examine whether the die is not « loaded » (whether the centre of gravity of this die is at its geometric centre, etc.). (p. 152)

Popper, K. (2012). The two fundamental problems of the theory of knowledge. London: Routledge Classics. (Originally published 1978)

Pierre Gréco sur scientificité et falsificationnisme

Aucune science de faits ne peut garantir ses décrets hors d’un champ de faits, c’est l’évidence, ni se dispenser d’expliciter la procédure qui en assure le contrôle ou la reproduction. Un fait ne prouve rien, bien entendu, et mille faits ne font qu’une chronique ; mais un fait peut démentir, et toute assertion qui ne se met pas en mesure d’être possiblement infirmée par des faits n’est pas une assertion scientifique. (p. 985)

Gréco, P. (1967). Épistémologie de la psychologie. In J. Piaget (Ed.). Logique et connaissance scientifique (pp. 927-991). Paris : Gallimard.

R. Duncan Luce on falsifiable psychological theories

Knowledge of an explicit, falsifiable psychological theory should not provide the (unaided) knower with the means to falsify it at will in every empirical context. Put another way, psychological theories should not turn to out to be nonfulfilling propheties any more than they should be fulfilling. In practice, this means that the scientist should be confident than an experimental or field design exists that allows the theory to be tested despite the subject’s knowledge of the theory. I call this the non-oxymoron criterion. (pp. 1-2)

Luce, R. D. (1995). Four tensions concerning mathematical modeling in psychology. Annual Review of Psychology, 46, 1-26.