. . . colors like a flourish of trumpets or pianissimo on the violin, great, calm, oscillating, splintered surgances . . . . Is this not form?
— Giacomo Puccini

Life is a constant oscillation between the sharp horns of dilemmas.
H. L. Mencken oscillations quote

The payment of debts is necessary for social order. The non-payment is quite equally necessary for social order. For centuries humanity has oscillated, serenely unaware, between these two contradictory necessities.
— Simone Weil

The psychoanalysis of individual human beings, however, teaches us with quite special insistence that the god of each of them is formed in the likeness of his father, that his personal relation to God depends on his relation to his father in the flesh and oscillates and changes along with that relation, and that at bottom God is nothing other than an exalted father.
— Sigmund Freud

The simplest single-celled organism oscillates to a number of different frequencies, at the atomic, molecular, sub-cellular, and cellular levels. Microscopic movies of these organisms are striking for the ceaseless, rhythmic pulsation that is revealed. In an organism as complex as a human being, the frequencies of oscillation and the interactions between those frequencies are multitudinous.
— oscillations quotation by George Leonard