Search results
- It was invented by Aristotle (384–322 B.C.) in Athens, and recorded in a group of writings known as the Organon.
library.biblicalarchaeology.org/department/origins-quod-erat-demonstrandum/
People also ask
Where did quod erat demonstrandum come from?
Why did Euclid use quod erat faciendum?
When was QED used in philosophy?
When was QED first used?
Philippe van Lansberge's 1604 Triangulorum Geometriæ used quod erat demonstrandum to conclude some proofs; others ended with phrases such as sigillatim deinceps demonstrabitur, magnitudo demonstranda est, and other variants.
The earliest known use of the phrase quod erat demonstrandum is in the early 1600s. OED's earliest evidence for quod erat demonstrandum is from 1614, in the writing of William Bedwell, Arabist and mathematician.
Etymology and early use. The phrase quod erat demonstrandum is a translation into Latin from the Greek Greek, Ancient (to 1453);: ὅπερ ἔδει δεῖξαι (Greek, Ancient (to 1453);: hoper edei deixai; abbreviated as ΟΕΔ). Translating from the Latin phrase into English yields "that was to be demonstrated".
In Dialogues Concerning Two New Sciences (1638) in Latin Galileo used quod erat intentum, quod erat demonstrandum, quod erat probandum, quod erat ostendendum, quod erat faciendum, quod erat determinandum, and quod erat propositum.
It originates from the Greek: hóper édei deîxai (ὅπερ ἔδει δεῖξαι), meaning "which had to be demonstrated". So the Latin Q.E.D. is a variation on the translation of the the expression used by the Greeks, namely, we know it was used by Euclid and Archimedes, and likely other Greek scholars who followed "suit."
The phrase originates from ancient Greek mathematics and philosophy, where demonstrating conclusions through rigorous proof was essential. In modern usage, Q.E.D. is still seen in academic writing, especially in mathematics, to affirm the validity of a proof. The expression underscores the commitment to logic and reason, emphasizing that claims ...
