Q0014
“A friend is another self.” — Aristotle (Nicomachean Ethics IX.4)
Verified English quotation. Primary source: Nicomachean Ethics IX.4. Theme: self.
English
A friend is another self.
Source and attribution
The archive attributes this English wording to Nicomachean Ethics IX.4 and files it under Peripatetic School. That locator distinguishes the passage from loose internet attributions: readers can return to the named work or section to check translation, surrounding argument, and edition-specific wording.
About Aristotle
Aristotle (384–322 BCE) was a Greek philosopher born in Stagira in Macedonia, the son of a court physician. At about seventeen he entered Plato’s Academy in Athens and remained associated with it until Plato’s death in 347.
Interpretation
Aristotle's formula in the Ethics compresses a longer account: a friend is someone who shares your life, whose good you pursue for their sake, and through whom you come to know yourself. Calling them another self is his way of explaining why friendship is necessary for happiness rather than optional — self-knowledge is difficult from the inside, and a friend makes it observable. The claim is not that friends are similar, which he elsewhere denies for some kinds of friendship.
Why it matters
It gives friendship a cognitive role: friends show you your own character from a position you cannot occupy, which is why the loss of one is a loss of self-knowledge.
Concepts in this quote
- Self
- Philosophy quotes about self explore identity, responsibility, and the examined life—from Socrates’ unexamined life to modern phenomenology and existential authenticity.
- Love
- Love in philosophy ranges from friendship and desire to care, justice, and the transformation of the self.
How to cite this quotation
APA: Aristotle. (n.d.). A friend is another self. In Philosophy Blind Box. https://www.philosophydef.com/quotes/q0014
MLA: Aristotle. “A friend is another self..” Philosophy Blind Box, https://www.philosophydef.com/quotes/q0014.
Chicago: Aristotle. “A friend is another self..” Philosophy Blind Box. Accessed 2026. https://www.philosophydef.com/quotes/q0014.
Frequently asked questions
What is the source of the quotation “A friend is another self.”?
The passage is attributed to Aristotle, Nicomachean Ethics IX.4. The archive attributes this English wording to Nicomachean Ethics IX.4 and files it under Peripatetic School. That locator distinguishes the passage from loose internet attributions: readers can return to the named work or section to check translation, surrounding argument, and edition-specific wording.
What does Aristotle mean by self?
To ask about the self is to ask what persists through experience, what can be known from the first-person point of view, and how character is formed. Some traditions treat the self as a substantial soul; others as a stream of experience, a social role, or a practical center of agency. This passage enters that discussion through self, love.