28. Although one can observe the scale of living beings at the point of view of organism, it is recognized that from the lichen to the tree, and from the zoophyte to man, there is a continuous chain elevating itself by degrees, in which all the links are joined together. Following step by step the series of beings, one can say that each species is a transformation of the species immediately below it. Since the body of man is in conditions identical with other bodies chemically and constitutionally, as he is born, lives, and dies in the same manner, he must have been formed in the same way.
