[75] thinking that the walls which are built around for the sake of protecting the fruit have been erected by the possessors of the land, and that the plants have been created for the sake of the production of fruit; thus, therefore, they said that in philosophy it is requisite for the consideration of the physical and the logical part of philosophy to be referred to the moral part, by which the moral character is improved, which has a desire at the same time for both the acquisition and the use of virtue.