|Modal Operators: modal operators are symbols for expressing possibility and necessity. These operators do not belong to classical logic, but fall into the field of modal logic. Their placement at the beginning or in the course of formulas determines the relative strength of statements that can be obtained from the interpretation of these formulas. See also range, stronger/weaker, modal logic, possible worlds.|
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Modal operator / problem of actuality / Field: Example, it is possible that a distance is twice or half:as big as it actually is - that can not be done by the possibility operator alone. - Incorrect solution: "actuality operator": which is to refer back to the actual world. - Modality: is used by the Relationism to express that double distance is possible, even if there is no matter point - The Substantivalism does not need that.
Modality / possibility // Physics / Field: a prefixed modal operator would change the content of a physical law. - ((s) which goes beyond the purely logical case p > Mp.)
Realism, Mathematics and Modality Oxford New York 1989
Truth and the Absence of Fact Oxford New York 2001
Science without numbers Princeton New Jersey 1980