Origin, Chapter 13, "Mutual affinities of organic beings..."

In the first part of this Chapter Darwin made the case that the Linnean system of classification was in fact based on common descent. He wrote:

From the first dawn of life, all organic beings are found to resemble each other in descending degrees, so that they can be classed in groups under groups … But what is meant by this system? Some authors look at it merely as a scheme for arranging together those living objects which are most alike…many naturalists…believe that it reveals the plan of the Creator; but unless it be specified whether order in time or space, or what else is meant by the plan of the Creator, it seems to me that nothing is thus added to our knowledge…

…I believe this element of descent is the hidden bond of connexion which naturalists have sought under the term of the Natural System.

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