Correlation does not imply causation ( cum hoc propter hoc , Latin for "with this, because of this") is a phrase used in science and statistics to emphasize that a correlation between two variables does not necessarily imply that one causes the other. [ 1 ] [ 2 ] Many statistical tests calculate correlation between variables . A few go further and calculate the likelihood of a true causal relationship; examples are the Granger causality test and convergent cross mapping . The opposite assumption, that correlation proves causation , is one of several questionable cause logical fallacies by which two events that occur together are taken to have a cause-and-effect relationship. This fallacy is also known as cum hoc ergo propter hoc , Latin for "with this, therefore because of this", and "false cause".
Post hoc ergo propter hoc , Latin for "after this, therefore because of this", is a logical fallacy (of the questionable cause variety) that states "Since that event followed this one, that event must have been caused by this one." It is often shortened to simply post hoc . It is subtly different from the fallacy cum hoc ergo propter hoc , in which two things or events occur simultaneously or the chronological ordering is insignificant or unknown, also referred to as false cause , coincidental correlation , or correlation not causation . Post hoc is a particularly tempting error because temporal sequence appears to be integral to causality .
The laws of thought are fundamental axiomatic rules upon which rational discourse itself is based. The rules have a long tradition in the history of philosophy and logic . They are laws that guide and underlie everyone's thinking, thoughts, expressions, discussions, etc. [ edit ] The Three Classical Laws The classical “Three Laws of Thought” are the three fundamental linguistic principles without which there could be no intelligible communication.
This article uses forms of logical notation. For a concise description of the symbols used in this notation, see List of logic symbols . In logic , the law of excluded middle (or the principle of excluded middle ) is the third of the three classic laws of thought .
This article uses forms of logical notation. 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.
This article uses forms of logical notation. For a concise description of the symbols used in this notation, see List of logic symbols . In logic , the law of identity is the first of the three classical laws of thought . It states that: “each thing is the same with itself and different from another”: “A is A and not ~A”. By this it is meant that each thing (be it a universal or a particular ) comprises it own unique set of characteristic qualities or features, which the ancient Greeks called its essence .
Buy a printable PDF in English and in French . Read the French version – Thanks to Gilles Peyroux. See a text-only version http://bit.ly/rhetological