請觀音經疏闡義鈔 1.86

1.86

「中道」下，標圓智。雖三觀一心，從勝彰名，故指中道，三皆名觀，復名智者。通而為論，觀智義一；別而往目，因果兩分。

From "the middle way" downward marks the wisdom of the perfect. Although the three contemplations are in a single mind, manifesting its name from the supreme, it indicates the middle way. All three are called contemplation, and are also called wisdom. Speaking generally, the meanings of contemplation and wisdom are one; looking at them separately, cause and effect are divided into two.