Axiom Quote by John Stuart Mill
“The maxim is, that whatever can be affirmed (or denied) of a class, may be affirmed (or denied) of everything included in the class. This axiom, supposed to be the basis of the syllogistic theory, is termed by logicians the dictum de omni et nullo.”
About This Quote
Source Book: A System of Logic, John Stuart Mill, 1843
A statement true of a whole class applies to each member, and vice versa, forming a logical principle.
In simple terms: What true of a group applies to each member.
Key Takeaway
Apply universal rules consistently.
Themes
logic
philosophy
reasoning
Mood
analytical
critical
Type
philosophical
educational
When to use this quote
- legal reasoning
- scientific classification
- ethical debates
- education curricula
Key Concepts
syllogism
universal quantification
Questions to Reflect On
- Do all members truly share the property?
- When does a universal claim fail?
A Different Perspective
Exceptions may arise when categories are not homogeneous.
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![“[For people] to refuse a hearing to an opinion, because they are sure that it is false, is to assume that their certainty is the same thing as absolute certainty. All silencing of discussion is an assumption of infallibility.” quote by John Stuart Mill](https://sms4smile.com/quotes/img-quotes/c53/john-stuart-mill-477_doubt_for-people-to-refuse-a-hearing-to-an-opi_63929.jpg)
