|Extrinsic, philosophy: intrinsic refers to properties that an object must have in order to be this object. This is not the same as the distinction between essential and non-essential properties. For example, the property of being known by many is an extrinsic property for a human. The person would be the same without this property. See also intrinsicness, essence, properties, features, necessity.|
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Extrinsic explanation/Loar/Field: E.g. when the role of numbers is only the role of names (descriptions) of properties of the physical system - then the properties of numbers will have no effect on the system - e.e. is often useful - but it must have an underlying intrinsic explanation.
Extrinsic explanation/Field: E.g. distance and angle size, use real numbers, but these are causally irrelevant - intrinsic e.: uses "betweenness" and congruence - (without numbers) - Numbers: are eliminated because they are causally ineffective - (as opposed to electrons) - Extrinsic explanation/Field: fruitless, if they are to be the final outcome - intrinsically: can be arbitrarily: E.g. standard meter.
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