Idea 5 of 12 c. 335 to 322 BCE until 2018

You become what you repeatedly do

Character is built by repeated actions: doing brave things makes you brave, and habits, once formed, run your life.

Said again in 4 books. 1 names Aristotle.

You have probably met this advice in a book about habits: you become what you repeatedly do. The idea is about 2,400 years old. The earliest source we can find is Aristotle’s Nicomachean Ethics, c. 335-322 BCE, which says that “by doing just actions we come to be just”. It has kept coming back since, in Benjamin Franklin’s Autobiography in 1791, William James’s The Principles of Psychology in 1890, Will Durant’s The Story of Philosophy in 1926 and James Clear’s Atomic Habits in 2018, and only Durant among them credits Aristotle. No book on this page argues against it.

An older hint may exist: Plato’s Republic 3.395d, possibly a few decades older, where imitation practised from youth becomes habit and second nature. We have not read that passage, and it is about imitation in education, so Nicomachean Ethics 2.1 is still the earliest source we can find.

c. 335 to 322 BCELink

Earliest we can find

Aristotle, Nicomachean Ethics 2.1

“exactly so, by doing just actions we come to be just; by doing the actions of self-mastery we come to be perfected in self-mastery; and by doing brave actions brave.”

Full text read.

Aristotle, Nicomachean Ethics 2.1, tr. D. P. Chase (1847).

Project Gutenberg eBook #8438, gutenberg.org/ebooks/8438.

Who said it again

Nothing from our reading list in between. The gap is ours, not history’s.

1791about 2,120 years laterLink

Benjamin Franklin, Autobiography

Echoes

Franklin sets out to “acquire the habitude of all these virtues” by practising them one at a time. He credits no one for the idea, and names Pythagoras only for daily examination, a different point.

“My intention being to acquire the habitude of all these virtues, I judg’d it would be well not to distract my attention by attempting the whole at once, but to fix it on one of them at a time”

Full text read.

Benjamin Franklin, Autobiography.

Project Gutenberg eBook #148, gutenberg.org/ebooks/148.

1890about 2,220 years laterLink

William James, The Principles of Psychology, ch. IV ‘Habit’

Echoes

James writes that we become saints “by so many separate acts and hours of work” and end as “walking bundles of habits”. He credits no one, naming Aristotle only for unrelated points.

“Could the young but realize how soon they will become mere walking bundles of habits, they would give more heed to their conduct while in the plastic state.”

Full text read.

William James, The Principles of Psychology, ch. IV ‘Habit’.

Project Gutenberg eBook #57628, gutenberg.org/ebooks/57628.

1926about 2,260 years laterLink

Will Durant, The Story of Philosophy

Cites Aristotle, per a summary

Wikiquote has Durant writing “we are what we repeatedly do” and “Excellence, then, is not an act but a habit”, built on passages he quotes from Aristotle’s Nicomachean Ethics, which he credits.

“‘these virtues are formed in man by his doing the actions’; we are what we repeatedly do. Excellence, then, is not an act but a habit”

Secondhand, from Wikiquote. Will Durant, The Story of Philosophy (1926).

This book is still in copyright, so we read an account of it, not the book.

Sources

Wikiquote: en.wikiquote.org/wiki/Will_Durant.

2018about 2,350 years laterLink

James Clear, Atomic Habits

Echoes, in his own writing

On jamesclear.com, Clear writes: “The more you repeat a behavior, the more you reinforce the identity associated with that behavior.” He credits no one for the idea.

“The more you repeat a behavior, the more you reinforce the identity associated with that behavior.”

Author’s own words, from jamesclear.com. James Clear, Atomic Habits (2018).

This book is still in copyright, so we read the author’s own words about it, not the book.

Sources

jamesclear.com: jamesclear.com/identity-votes.

2012

Still being checked

Charles Duhigg, The Power of Habit

We have one account of this book that we may read, and it gives its own words, not the book’s. A second account that agrees would bring the link back.

Next idea

06 Small steps add up

How this page was made. AI agents did the reading. Each link was judged by two readers from different AI models, working blind; a third settled their splits (4 of 4 links on this page needed no tiebreak). Every quote was checked word for word against its source. “Full text read” means the agents read the book itself; “Author’s own words” means the author’s free writing elsewhere; “Secondhand” means a free summary or article about the book.

The letter

One idea a week, followed across time.

No. 1Small steps add up