§ 18 Conclusion of Chapter
After all however, good stones and well tempered tools apart, the one thing essential is the art, the intelligence, and the judgement of those who use them, for there is the greatest difference between artists, although they may all use the same method, as to the measure of grace and beauty they impart to the works which they execute. This enables us to discern and to recognize the perfection of the work done by those who really understand, as opposed to that of others who know less. As, therefore, all the excellence and beauty of the things most highly praised consist in that supreme perfection given to them by those who understand and can judge, it is necessary to strive with all diligence always to make things beautiful and perfect—nay rather, most beautiful and most perfect.