Single Idea 6939

[catalogued under 26. Natural Theory / B. Natural Kinds / 2. Defining Kinds]

Full Idea

The guiding principle is that what is true of one piece of copper is true of another; such a guiding principle with regard to copper would be much safer than with regard to many other substances - brass, for example.

Clarification

Copper is a an element; brass can come in different proportions in the mixture

Gist of Idea

What is true of one piece of copper is true of another (unlike brass)

Source

Charles Sanders Peirce (The Fixation of Belief [1877], p. 8)

Book Reference

Peirce,Charles Sanders: 'Philosophical Writings of Peirce', ed/tr. Buchler,Justus [Dover 1940], p.8


A Reaction

Peirce is so beautifully simple and sensible. This gives the essential notion of a natural kind, and is a key notion in our whole understanding of physical reality.

Related Idea

Idea 8153 By knowing one piece of clay or gold, you know all of clay or gold [Anon (Upan)]