“By a clock we understand anything characterized by a phenomenon passing periodically through identical phases so that we must assume, by the principle of sufficient reason, that all that happens in a given period is identical with all that happens in an arbitrary period.”
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Probable attribution
A source trail connects this quotation to Albert Einstein and "Principe de relativité" Archives des sciences physiques et naturelles (1910) ser. 4. 29 5-28 pp. 125–244, as quoted by Julian Barbour, "The Nature of Time" (Mar 20, 2009) p. 7, arXiv:0903.3489., but the exact English wording has not been confirmed in a primary text. The attribution is therefore probable rather than definitive.
Likely origin: "Principe de relativité" Archives des sciences physiques et naturelles (1910) ser. 4. 29 5-28 pp. 125–244, as quoted by Julian Barbour, "The Nature of Time" (Mar 20, 2009) p. 7, arXiv:0903.3489.
Review the attribution sourceAbout this quote
This page records the wording "By a clock we understand anything characterized by a phenomenon…," which centers on clock, understand, anything. A concrete trail points toward Einstein, but the exact English form remains unconfirmed; the page therefore labels it as attributed to him while preserving its education and philosophy context.
When to use it
- Use "By a clock we understand anything characterized by a phenomenon…" in a education discussion, then ask which concrete claim the wording makes.
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