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Cum Hoc Ergo Propter Hoc. The counter assumption, that correlation proves causation, is considered a questionable cause logical fallacy in that two events occurring together are taken to have a cause-and-effect relationship.

Cum Hoc Ergo Propter Hoc



Post Hoc Ergo Propter Hoc

" It is often shortened to simply post hoc. It is subtly different from the fallacy cum hoc ergo propter hoc (correlation does not imply causation), in which two things or events occur simultaneously or the chronological ordering is insignificant or unknown. Post hoc is a particularly tempting error because temporal sequence appears to be integral to causality.

The fallacy lies in coming to a conclusion based solely on the order of events, rather than taking into account other factors that might rule out the connection. Pattern[edit] The form of the post hoc fallacy can be expressed as follows: A occurred, then B occurred.Therefore, A caused B. When B is undesirable, this pattern is often extended in reverse: Avoiding A will prevent B. Examples[edit] In popular culture[edit] Law of Thought. The laws of thought are fundamental axiomatic rules upon which rational discourse itself is often considered to be based.

Law of Thought

The formulation and clarification of such rules have a long tradition in the history of philosophy and logic. Generally they are taken as laws that guide and underlie everyone's thinking, thoughts, expressions, discussions, etc. According to the 1999 Cambridge Dictionary of Philosophy,[1] laws of thought are laws by which or in accordance with which valid thought proceeds, or that justify valid inference, or to which all valid deduction is reducible. Laws of thought are rules that apply without exception to any subject matter of thought, etc.; sometimes they are said to be the object of logic. Law of Excluded Middle. Law of Noncontradiction. This article uses forms of logical notation.

Law of Noncontradiction

For a concise description of the symbols used in this notation, see List of logic symbols. In classical logic, the law of non-contradiction (LNC) (or the law of contradiction (PM) or the principle of non-contradiction (PNC), or the principle of contradiction) is the second of the three classic laws of thought. It states that contradictory statements cannot both be true in the same sense at the same time, e.g. the two propositions "A is B" and "A is not B" are mutually exclusive. The principle was stated as a theorem of propositional logic by Russell and Whitehead in Principia Mathematica as: Law of Identity. This article uses forms of logical notation.

Law of Identity

For a concise description of the symbols used in this notation, see List of logic symbols. In logical discourse, violations of the Law of Identity (LOI) result in the informal logical fallacy known as equivocation.[5] That is to say, we cannot use the same term in the same discourse while having it signify different senses or meanings – even though the different meanings are conventionally prescribed to that term. In everyday language, violations of the LOI introduce ambiguity into the discourse, making it difficult to form an interpretation at the desired level of specificity. History[edit] Socrates: How about sounds and colours: in the first place you would admit that they both exist? Aristotle takes recourse to the law of identity - though he does not identify it as such - in an attempt to negatively demonstrate the law of non-contradiction.

Both Thomas Aquinas (Met. John Locke (Essay Concerning Human Understanding IV. vii. iv. People[edit] Rhetological Fallacies. Thanks to 李为维, Hayanna Carvalho, Iván Galarza, Klaus-Michael Lux, Kadar Magor, Gilles Peyroux and Adriano Venditti, Rhetological Fallacies is now available in Chinese, French, German, Hungarian, Italian, Portuguese, Romanian and Spanish.

Rhetological Fallacies