Tolstoy, Leo.
The first step : an essay on the morals of diet, to which are added two stories. (Manchester : Albert Broadbent, 1899).
https://archive.org/details/firststepanessa00maudgoog.
"All moral teachings set up a ladder, as the Chinese wisdom puts it, reaching from earth to heaven, the ascent of which can only be accomplished by starting from the lowest step. As in the teaching of the Brahmins, Buddhists, Confucians, so also in the teaching of the Greek sages, steps were fixed, and a superior step could not be attained without the lower one having
been previously taken."