Franklin began the Autobiography in 1771 as a letter to his son, writing from a bishop's country house in England. He frames the whole as a printer's second edition: he cannot live his life again, but he can set down the means by which an obscure Boston tallow-chandler's son arrived at 'affluence and some degree of reputation in the world,' hoping that posterity may find some of them fit to be imitated.
The early sections trace a self-education assembled from scraps. Franklin buys books with every spare coin, borrows volumes from a bookseller's apprentice, imitates the Spectator by turning its essays into verse and back into prose, and teaches himself arithmetic, navigation, and Locke's epistemology in the margins of a printer's working day. The discipline he imposes on himself is already visible here: he takes up a vegetarian diet partly because it buys him solitary study time while his fellow apprentices are at their midday meal.
The moral centerpiece of the book is Franklin's project of arriving at moral perfection, conceived around 1728. He lists thirteen virtues, each with a short governing precept: Temperance, Silence, Order, Resolution, Frugality, Industry, Sincerity, Justice, Moderation, Cleanliness, Tranquillity, Chastity, and Humility (added on advice from a Quaker friend who told him he was thought proud). He makes a small ruled book, gives each virtue a page, divides each page into seven columns for the days of the week, and marks every evening whatever fault he has committed. He takes the virtues in sequence, spending a week on each, turning the thirteen-virtue cycle four times in a year. He is surprised to find himself fuller of faults than he imagined, but he has the satisfaction of seeing them diminish.
Franklin is candid about failure. Order proves nearly incorrigible throughout his life. He acknowledges the 'errata' of his youth (using money held in trust, neglecting Miss Read, publishing a reckless philosophical pamphlet) and calls them by the printer's term without either false modesty or self-excuse. He nevertheless credits the endeavour itself, writing late in life that, though he never arrived at the perfection he sought, he was by the endeavour a better and a happier man than he would otherwise have been.
The later parts of the Autobiography record how the same virtues that produced personal ease produced civic institutions. The Junto, a mutual-improvement club of young tradesmen, becomes the seedbed of the Philadelphia subscription library, the first in the colonies. Industry and frugality free Franklin from debt early enough that he can retire from active printing at forty-two and devote himself to science and public affairs. The book breaks off in 1757, leaving his diplomatic career unwritten, but the shape of the argument is complete: character is made by method, and good institutions are made by men of good character.