“Everything has a price.”

Source: The Alchemist

Im Reiche der Zwecke hat alles entweder einen Preis oder eine Würde. Was einen Preis hat, an dessen Stelle kann auch etwas anderes als Äquivalent gesetzt werden; was dagegen über allen Preis erhaben ist, mithin kein Äquivalent verstattet, das hat eine Würde.
434:32, M. Gregor, trans. (Cambridge: 1998), p. 42
Groundwork of the Metaphysics of Morals (1785)

Oscar Iden Lecture Series, Lecture 3: "The State of Individuals" (1976)

Audio lectures, Dangers Inherent in Public Education (March 24, 1986)

Lord Darlington, Act III.
Lady Windermere's Fan (1892)
Variant: What is a cynic? A man who knows the price of everything and the value of nothing.
Source: The Picture of Dorian Gray
Context: A man who knows the price of everything and the value of nothing. [Answering the question, what is a cynic? ]

Costly Grace, p 43.
Costly Grace
Context: Cheap grace is the deadly enemy of our Church. We are fighting to-day for costly grace. Cheap grace means grace sold on the market like cheapjacks’ wares. The sacraments, the forgiveness of sin, and the consolations of religion are thrown away at cut prices. Grace is represented as the Church’s inexhaustible treasury, from which she showers blessings with generous hands, without asking questions or fixing limits. Grace without price; grace without cost! The essence of grace, we suppose, is that the account has been paid in advance; and, because it has been paid, everything can be had for nothing. Since the cost was infinite, the possibilities of using and spending it are infinite. What would grace be if it were not cheap?

Source: The Summer Garden

Source: An Autobiography

Manuscript Found in Accra (2012), What should survivors tell their children?