Ipso facto is a Latin phrase, directly translated as "by the fact itself," which means that a certain phenomenon is a direct consequence, a resultant effect, of the action in question, instead of being brought about by a previous action. It is a term of art used in philosophy, law, and science. An example in law is money laundering: the act is not ipso facto illegal because it is an exchange but is done as a cover for something else, so the act puts the actions of an individual in question. A common English idiom with a similar meaning is "in and of itself".
Aside from its technical uses, it occurs frequently in literature, particularly in scholarly addenda: e.g., "Faustus had signed his life away, and was, ipso facto, incapable of repentance" (re: Christopher Marlowe, The Tragical History of Dr. Faustus) or "These prejudices are rooted in the idea that every tramp ipso facto is a blackguard" (re: George Orwell, Down and Out in Paris and London).
In religion 
Ipso facto denotes the automatic character of the loss of membership in a religious body by someone guilty of a specified action. Within the Roman Catholic Church, the phrase latae sententiae is more commonly used than ipso facto with regard to ecclesiastical penalties such as excommunication. It indicates that the effect follows even if no verdict (in Latin, sententia) is pronounced by an ecclesiastical superior or tribunal.
See also 
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