|Qualities, philosophy: quality is an expression of the nature of objects or the form of properties. Today, it is no longer understood as a category but rather as the sum of the distinguishing features of an object. Properties of the objects like their size, mass, etc. count as objective or primary qualities, subjective (secondary) qualities are properties which are settled in the subject, e.g. color. See also quantities, qualia, subjectivity, objectivity, properties, features.|
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Primary quality/Duhem: is actually, but not by law an irreducible quality.
We only realize that we are not able to disassemble a quality further.
Ziel und Struktur der physikalischen Theorien Hamburg 1998