"The happiness of your life depends upon the quality of your thoughts: therefore, guard accordingly, and take care that you entertain no notions unsuitable to virtue and reasonable nature"
About this Quote
The intent is practical, almost bureaucratic: if thoughts are the inputs, your life is the output. Stoicism turns happiness into quality control. “Guard accordingly” frames the mind as a site of constant threat - not from enemies across a border, but from internally generated stories: resentment, self-pity, fantasies of control. The subtext is a rebuke to the common excuse that circumstances “make” us miserable. Marcus has circumstances that would crush most people. His wager is that misery often arrives as an interpretation first.
The phrase “no notions unsuitable to virtue and reasonable nature” is where the ideology shows. This isn’t modern “positive thinking.” It’s moral and civic. Virtue is the standard, reason is the filter, and “nature” is the reminder that the world isn’t obliged to cooperate. If your thoughts align with what a rational, socially responsible human should do, happiness follows not as pleasure but as steadiness - a calm earned by refusing to let the mind become a rumor mill about everything you can’t control.
Quote Details
| Topic | Wisdom |
|---|---|
| Source | Help us find the source |
| Cite |
Citation Formats
APA Style (7th ed.)
Aurelius, Marcus. (2026, January 17). The happiness of your life depends upon the quality of your thoughts: therefore, guard accordingly, and take care that you entertain no notions unsuitable to virtue and reasonable nature. FixQuotes. https://fixquotes.com/quotes/the-happiness-of-your-life-depends-upon-the-33330/
Chicago Style
Aurelius, Marcus. "The happiness of your life depends upon the quality of your thoughts: therefore, guard accordingly, and take care that you entertain no notions unsuitable to virtue and reasonable nature." FixQuotes. January 17, 2026. https://fixquotes.com/quotes/the-happiness-of-your-life-depends-upon-the-33330/.
MLA Style (9th ed.)
"The happiness of your life depends upon the quality of your thoughts: therefore, guard accordingly, and take care that you entertain no notions unsuitable to virtue and reasonable nature." FixQuotes, 17 Jan. 2026, https://fixquotes.com/quotes/the-happiness-of-your-life-depends-upon-the-33330/. Accessed 9 Feb. 2026.












