particular phase of the god’s activity.  Such an adjective was called a cognomen, and was often of very great importance because it began to be felt that a god with one adjective, i.e. invoked for one purpose, was almost a different god from the same god with a different adjective, i.e. invoked for another purpose.  Thus a knowledge of these adjectives was almost as necessary as a knowledge of the name of the god.  The next step in the development was one which followed very easily.  These important adjectives began to be thought of as having a value and an existence in themselves, apart from the god to which they were attached.  The grammatical change which accompanied this psychological movement was the transfer of the adjective into an abstract noun.  Both adjectives and abstract nouns express quality, but the adjective is in a condition of dependence on a noun, while the abstract noun is independent and self-supporting.  And thus, just as in certain of the lower organisms a group of cells breaks off and sets up an individual organism of its own, so in old Roman religion some phase of a god’s activity, expressed in an adjective, broke off with the adjective from its original stock and set up for itself, turning its name from the dependent adjective form into the independent abstract noun.  Thus Juppiter, worshipped as a god of good faith in the dealings of men with one another, the god by whom oaths were sworn under the open sky, was designated as “Juppiter, guarding-good-faith,” Juppiter Fidius.  There were however many other phases of Juppiter’s work, and hence the adjective fidius became very important as the means of distinguishing this activity from all the others.  Eventually it broke off from Juppiter and formed the abstract noun Fides, the goddess of good faith, where the sex of the deity as a goddess was entirely determined by the grammatical gender of abstract nouns as feminine.

This is all strange enough but there is one more step in the development even more curious yet.  This abstract goddess Fides did not stay long in the purely abstract sphere; she began very soon to be made concrete again, as the Fides of this particular person or of that particular group and as this Fides or that, until she became almost as concrete as Juppiter himself had been, and hence we have a great many different Fides in seeming contradiction to the old grammatical rule that abstract nouns had no plural.  Now all this development in the field of religion throws light upon the character of the Roman mind and its instinctive methods of thought, and we see why it is that the Romans were very great lawyers and very mediocre philosophers.  Both law and philosophy require the ability for abstract thought; in both cases the essential qualities of a thing must be separated from the thing itself.  But in the case of philosophic thought this abstraction, these qualities, do not immediately seek reincarnation.