- Every picture is a collection of units or items.
- Every unit has a given value.
- The value of a unit depends on its attraction, and its attraction varies according to placement.
- A unit near the edge has more attraction than the same unit at the middle.
- Every part of the picture space has some attraction.
- Space without detail may possess attraction by gradation and by suggestion.
- A unit of attraction in an otherwise empty space has more weight through isolation than when placed with other units.
- A black unit on white or a white unit on black has more attraction than the same unit on grey.
- The value of a black or white unit is proportionate also to the size of the space that contrasts with it.
- A unit in the foreground has less weight than the same one in the distance.
- Two or more associated units may be reckoned as one. Their united central point is the point on which they balance with others.
from “Composition in Art” by Henry Rankin Poore, page 10.