which the same things could be distributed [...] A classification thus formed is properly scientific or philosophical, and is commonly called a Natural, in contradistinction to a Technical or Artificial, classification or arrangement (Mill 1872, 499)." Ridley (1986) provided the following definitions: "artificial classification. The term (like its opposite, natural classification) has many meanings; in this book I have picked a phenetic meaning. A classificatory group will be defined by certain characters, called defining characters; in an artificial classification, the members of a group resemble one another in their defining characters (as they must, by definition) but not in their non-defining characters. With respect to the characters not used in the classification, the members of a group are uncorrelated. "natural classification. Classificatory groups are defined by certain characters, called 'defining' characters; in a natural group, the members of the group resemble one another for non-defining characters as well as for the defining character. This is not the only meaning for what is perhaps the most variously used term in taxonomy ... Taxonomic monism vs. pluralism Stamos (2004, 138) wrote: "The fact is, modern scientists classify atoms into elements based on proton number rather than anything else because it alone is the causally privileged factor [gold is atomic number 79 in the periodic table because it has 79 protons in its nucleus]. Thus nature itself has supplied the causal monistic essentialism. Scientists in their turn simply discover and follow (where "simply" ≠ "easily")." See also Biological classification Categorization Chemical classification Classification theorem Folk taxonomy Library classification Medical classification Statistical classification Taxonomy (general) References External links Parrochia, Daniel 2016. "Classification". In The Internet Encyclopedia of Philosophy eds. James Fieser and Bradley Dowden. Theories Classification systems