Supposition
In the logic of scholasticism, supposition is used to denote various ways in which a term can stand or denote something. A presentation of these different types is also known as the supposition theory .
A theory of supposition is found in many treatises of medieval logic and in most sums of logic, such as those of Wilhelm von Ockham , Wilhelm von Sherwood, and Walter Burleigh . The following is the essence of these theories, what most medieval authors would agree on.
The supposition relates to terms, i.e. general concepts such as those found in the syllogism . For example, in the sentence "homo est animal", "man is a sense being", both "homo" and "animal" are terms. The following types of supposition are now distinguished:
- suppositio materialis - material supposition : A term stands for this itself or for the word that forms the term. Example “ homo est nomen” - “'Mensch' is a noun”. Here the term "homo" stands for the word "homo" itself.
- suppositio simplex - simple supposition : A term stands for the term it denotes . Example “homo est species” - “Man is a species”. The term "homo" stands for the human species as such.
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suppositio personalis - personal supposition describes the normal case, namely that a term stands for its individual instances, for example "human" for the individual human being. The personal supposition in turn has different subspecies, depending on whether the term denotes all or only some of these instances:
- suppositio determinata - certain supposition : A term stands for a totality in such a way that the sentence can be transformed into a disjunction (or connection) in which the individual elements are enumerated. Example: In the sentence “aliquis homo currit” - “some person is running”, “homo” / “person” is used in a certain supposition. This sentence is equivalent to "Caesar currit vel Cicero currit vel ..." - "Caesar runs or Cicero runs or ..." etc. for all individual instances for "human".
- suppositio confusa distributiva - confused-distributed supposition : A term stands for all elements of a totality, in such a way that the sentence can be transformed into a conjunction (and connection), which explicitly lists the individual elements. Example: in the sentence “omnis homo currit” - “everyone runs”, “homo” / “human” stands in a confused, distributed supposition. The sentence can be transformed into "Caesar currit et Cicero currit et ..." - "Caesar runs and Cicero runs and ..." etc. for all individual instances for "human".
- suppositio confusa tantum - just confused supposition : a term stands for an element of a totality, but the sentence cannot be transformed into either a conjunction or a disjunction. Example "Omnis Romanus est homo" - "Every Roman is a person". The term “homo” / “man” is merely a confused supposition, because the sentence is neither equivalent to “Omnis Romanus est Caesar vel Cicero vel ...” - “Every Roman is Caesar or Cicero or ...” nor equivalent with "Omnis Romanus est Caesar et Cicero et ..." - "Every Roman is Caesar and Cicero and ...".
According to others, the medieval doctrine of supposition fell into disrepute as scholastic in the early modern period and was forgotten. Presumably therefore it cannot be mapped directly to a question of modern logic. Instead, there is a whole range of current issues linked to supposition theory. The material supposition is reminiscent of today's considerations on the quotation , the differentiation of formal and material supposition is thus in the matter the forerunner of the distinction between metalanguage and object language or in Anglo-Saxon (language) philosophy and linguistics of “use” and “mention”.
The simple supposition suggests a theory of abstract objects . Furthermore, there is a connection between personal supposition and the modern doctrine of quantification . According to the modern view, generality and particularity of quantifiers such as “all” and “some” (“omnis”, “aliquid”) are not attached to the terms (modern: predicates ).