“The materials of action are variable, but the use we make of them should be constant.”
How Nobleness of Mind may be consistent with Prudence, Chap. v.
Bartlett's Familiar Quotations, 10th ed. (1919)
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Epictetus 175
philosopher from Ancient Greece 50–138Related quotes

§4
Introduction to the Analysis of the Infinite (1748)

“Construction methods are… variable for each specific material.”
p, 125
Philosophy of Structures (1958)

Joseph Butler, Human Nature and Other Sermons, "Sermon VII" as quoted in Arnold's "St. Paul and Protestantism" (1870).
Misattributed

“The greatest mistake we make is living in constant fear that we will make one.”

“No one should be discouraged, Theaetetus, who can make constant progress, even though it be slow.”
Original Greek, from Sophist 261b http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0172%3Atext%3DSoph.%3Asection%3D261b: θαρρεῖν, ὦ Θεαίτητε, χρὴ τὸν καὶ σμικρόν τι δυνάμενον εἰς τὸ πρόσθεν ἀεὶ προϊέναι.
Also quoted in variant forms such as: Never discourage anyone who continually makes progress, no matter how slow
Sophist