Feature

A feature is an attribute or characteristic of something. Every concept has features; every material has features; even a feature itself has features. The most important feature of a feature is named "value." All features have value.

A feature is a concept, so we already know a great deal about it. Concepts have features by which we identify, describe, and distinguish one from another: a name, a definition, and others. Since "feature" is itself a concept, it inherits these. And it adds its own most-important feature: a value. The value of a feature may be qualitative, expressed in words, or quantitative, expressed as a magnitude or multitude. Quantitative values may be fixed or variable; fixed values are called quantities and variable values are called variables.

All physical materials have a set of features by which they can be characterized. These features are independent of human awareness of them. They include both static features and dynamic features. The dynamic features are referred to as behaviors. We see materials, measure them, describe them because of their features.

Where the description ends, the property begins. A feature is what something has; a property is what we say about that feature when we attach a value to it. This is the discipline at the center of macroscopic chemistry: a thing has features; a named, valued description of a feature is a property of that thing.