Q0049
“Plurality should not be posited without necessity.” — William of Ockham (Summa Logicae et al. (principle))
Verified English quotation. Primary source: Summa Logicae et al. (principle). Theme: reason.
English
Plurality should not be posited without necessity.
Source and attribution
The archive attributes this English wording to Summa Logicae et al. (principle) and files it under Scholasticism. 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 William of Ockham
William of Ockham (c. 1287–1347) was an English Franciscan philosopher-theologian associated with late medieval nominalism.
Interpretation
Ockham's principle is a methodological rule rather than a claim about the world. It says not to multiply entities beyond what explanation requires, so where a simpler account suffices, the additional postulate is unwarranted. It functions as a tie-breaker between theories rather than as proof that the simpler one is true. He applied it mainly to reject unnecessary metaphysical apparatus in his predecessors.
Why it matters
Used properly it chooses between adequate explanations, not between an explanation and none. It is often misused to dismiss the unfamiliar simply for being unfamiliar.
Concepts in this quote
- Reason
- Reason is the capacity to give and assess reasons—central to logic, science, ethics, and public argument.
- Method
- Method appears in this archive as a live philosophical concern—not a slogan. These verified English passages show how thinkers treat method as a problem of judgment, practice, or explanation.
How to cite this quotation
APA: William of Ockham. (n.d.). Plurality should not be posited without necessity. In Philosophy Blind Box. https://www.philosophydef.com/quotes/q0049
MLA: William of Ockham. “Plurality should not be posited without necessity..” Philosophy Blind Box, https://www.philosophydef.com/quotes/q0049.
Chicago: William of Ockham. “Plurality should not be posited without necessity..” Philosophy Blind Box. Accessed 2026. https://www.philosophydef.com/quotes/q0049.
Frequently asked questions
What is the source of the quotation “Plurality should not be posited without necessity.”?
The passage is attributed to William of Ockham, Summa Logicae et al. (principle). The archive attributes this English wording to Summa Logicae et al. (principle) and files it under Scholasticism. 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 William of Ockham mean by reason?
Philosophers disagree about whether reason is the slave of the passions, the legislator of morality, or one tool among others. The quotations here keep that disagreement in play. This passage enters that discussion through reason, method.