[Benjamin Franklin]identified thirteen virtues he wanted to cultivate--temperance, silence, order, resolution, frugality, industry, sincerity, justice, moderation, cleanliness, tranquility, chastity and humility--and made a chart with those virtues plotted against the days of the week. Each day, Franklin would score himself on whether he practiced those thirteen virtues.
Gretchen Rubin (2009). “The Happiness Project: Or, Why I Spent a Year Trying to Sing in the Morning, Clean My Closets, Fight Right, Read Aristotle, and Generally Have More Fun”, p.8, Harper Collins