- prediction paradox
- The teacher and the class know that the last day of term is Friday. A week before, the teacher tells the class that before the end of term there will be an unexpected examination: the pupils will not know, the evening before, that the examination will occur on the following day. It seems plain that the teacher can set such an examination. But the bright pupil argues as follows. The examination cannot be on the final Friday. For then we would know, on the Thursday evening, that it had to be on that day. So the teacher's effective period, within which the examination must be set, ends on the Thursday. But then we know, on the Wednesday evening, that (since Friday is already excluded) it must be on Thursday. This contradicts the condition again. So the teacher cannot wait until Thursday. By similar reasoning we can show that there is no day on which the examination can be set.
Philosophy dictionary. Academic. 2011.
Look at other dictionaries:
Unexpected hanging paradox — The unexpected hanging paradox is an alleged paradox about a prisoner s response to an unusual death sentence. It is alternatively known as the hangman paradox, the fire drill paradox, or the unexpected exam (or pop quiz) paradox.Despite… … Wikipedia
examination paradox — See prediction paradox … Philosophy dictionary
unexpected examination paradox — See prediction paradox … Philosophy dictionary
Newcomb's paradox — Newcomb s paradox, also referred to as Newcomb s problem, is a thought experiment involving a game between two players, one of whom purports to be able to predict the future. Whether the problem is actually a paradox is disputed. Newcomb s… … Wikipedia
Loschmidt's paradox — Loschmidt s paradox, also known as the reversibility paradox, is the objection that it should not be possible to deduce an irreversible process from time symmetric dynamics. This puts the time reversal symmetry of (almost) all known low level… … Wikipedia
Perceptual paradox — A Perceptual paradox illustrates the failure of a theoretical prediction. Theories of perception are supposed to help a researcher predict what will be perceived when senses are stimulated.A theory usually comprises a Mathematical model (formula) … Wikipedia
Twin paradox — In physics, the twin paradox is a thought experiment in special relativity, in which a twin makes a journey into space in a high speed rocket and returns home to find he has aged less than his identical twin who stayed on Earth. This result… … Wikipedia
Raven paradox — The Raven paradox, also known as Hempel s paradox or Hempel s ravens is a paradox proposed by the German logician Carl Gustav Hempel in the 1940s to illustrate a problem where inductive logic violates intuition. It reveals the problem of… … Wikipedia
Predestination paradox — A predestination paradox (also called causal loop, causality loop, and, less frequently, closed loop or closed time loop) is a paradox of time travel that is often used as a convention in science fiction. It exists when a time traveller is caught … Wikipedia
French paradox — The French paradox refers to the observation that the French suffer a relatively low incidence of coronary heart disease, despite having a diet relatively rich in saturated fats.Ferrieres, J. (2004). The French Paradox; Lessons for other… … Wikipedia