De Plantatione

These duties which are as it were in the middle, appear to me to be properly looked upon in the same light as those trees, which admit of being cultivated and used for food; for each of them bears most useful fruits, the one for the body, and the other for the soul. But in the middle there must necessarily be many injurious plants springing up with and growing along-side of them, which must be removed in order that the better sorts may not be injured.