[Illustration:  Diagram XXVII.

ILLUSTRATING HOW INTEREST MAY BALANCE MASS]

[Sidenote:  Between Variety and Unity.]

And lastly, there must be a balance struck between variety and unity.  A great deal has already been said about this, and it will only be necessary to recapitulate here that to variety is due all the expression or the picturesque, of the joyous energy of life, and all that makes the world such a delightful place, but that to unity belongs the relating of this variety to the underlying bed-rock principles that support it in nature and in all good art.  It will depend on the nature of the artist and on the nature of his theme how far this underlying unity will dominate the expression in his work; and how far it will be overlaid and hidden behind a rich garment of variety.

But both ideas must be considered in his work.  If the unity of his conception is allowed to exclude variety entirely, it will result in a dead abstraction, and if the variety is to be allowed none of the restraining influences of unity, it will develop into a riotous extravagance.

XVI

RHYTHM:  PROPORTION

Rules and canons of proportion designed to reduce to a mathematical formula the things that move us in beautiful objects, have not been a great success; the beautiful will always defy such clumsy analysis.  But however true it is that beauty of proportion must ever be the result of the finer senses of the artist, it is possible that canons of proportion, such as those of the human body, may be of service to the artist by offering some standard from which he can depart at the dictates of his artistic instinct.  There appears to be no doubt that the ancient sculptors used some such system.  And many of the renaissance painters were interested in the subject, Leonardo da Vinci having much to say about it in his book.

Like all scientific knowledge in art, it fails to trap the elusive something that is the vital essence of the whole matter, but such scientific knowledge does help to bring one’s work up to a high point of mechanical perfection, from which one’s artistic instinct can soar with a better chance of success than if no scientific scaffolding had been used in the initial building up.  Yet, however perfect your system, don’t forget that the life, the “dither,” will still have to be accounted for, and no science will help you here.

The idea that certain mathematical proportions or relationships underlie the phenomena we call beauty is very ancient, and too abstruse to trouble us here.  But undoubtedly proportion, the quantitative relation of the parts to each other and to the whole, forms a very important part in the impression works of art and objects give us, and should be a subject of the greatest consideration in planning your work.  The mathematical relationship of these quantities is a subject that has always fascinated scholars, who