| 11091 | You can bathe in the same river twice, but not in the same river stage [Quine on Heraclitus] |
| Full Idea: You can bathe in the same river twice, but not in the same river stage. | |
| From: comment on Heraclitus (fragments/reports [c.500 BCE]) by Willard Quine - Identity, Ostension, and Hypostasis 1 | |
| A reaction: This seems to make Quine a 'perdurantist', committed to time-slices of objects, rather than whole objects enduring through change. |
| 427 | It is not possible to step twice into the same river [Heraclitus] |
| Full Idea: It is not possible to step twice into the same river. | |
| From: Heraclitus (fragments/reports [c.500 BCE], B091), quoted by Plutarch - 24: The E at Delphi 392b10- |
| 579 | Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle] |
| Full Idea: Cratylus was appalled that Heraclitus said you could not step twice into the same river, because it was already going too far to admit stepping into the same river once. | |
| From: report of Cratylus (fragments/reports [c.425 BCE]) by Aristotle - Metaphysics 1010a | |
| A reaction: Compare Idea 427. |
| 16793 | A thing is (less properly) the same over time if each part is succeeded by another [Buridan] |
| Full Idea: Less properly, one thing is said to be numerically the same as another according to the continuity of distinct parts, one in succession after another. In this way the Seine is said to be the same river after a thousand years. | |
| From: Jean Buridan (Questions on Aristotle's Physics [1346], I.10, f. 13vb), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 29.3 | |
| A reaction: This is a rather good solution to the difficulty of the looser non-transitive notion of a thing being 'the same'. The Ship of Theseus endures (in the simple case) as long as you remember to replace each departing plank. Must some parts be originals? |
| 17257 | It is the same river if it has the same source, no matter what flows in it [Hobbes] |
| Full Idea: That will be the same river which flows from one and the same fountain, whether the same water, or other water, or something other than water, flow thence. | |
| From: Thomas Hobbes (De Corpore (Elements, First Section) [1655], 2.11.07) | |
| A reaction: This makes the source the one necessity for a river. I think the end matters too. If the Thames reversed direction, and flowed into Wales, it would not be the Thames any more. |
| 21303 | We accept the identity of a river through change, because it is the river's nature [Hume] |
| Full Idea: Where the objects are in their nature changeable and inconstant, we admit of a more sudden transition. The nature of a river consists in the motion and change of parts. What is expected appears of less moment than what is unusual and extraordinary. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Aha! Little does Hume realise how Aristotelian he is! Aristotle may have a more objective view of the 'nature' of a thing, but making inferences about identity over time from a thing's essential nature is pure Aristotle. |
| 15256 | Humeans cannot step in the same river twice, because they cannot strictly form the concept of 'river' [Harré/Madden] |
| Full Idea: A Humean cannot step in the same river twice, not because the river is always a different river, but because he can strictly have no such concept as 'river'. | |
| From: Harré,R./Madden,E.H. (Causal Powers [1975], 4.II) | |
| A reaction: This arises from a discussion of induction. What is a Humean to make of an object which keeps changing? They only have connected impressions, and no underlying essence to hold the impressions together. |
| 3351 | One can step into the same river twice, but not into the same water [Benardete,JA] |
| Full Idea: One can step into the same river twice, but one must not expect to step into the same water. | |
| From: José A. Benardete (Metaphysics: the logical approach [1989], Ch.21) |
| 21632 | A river is not just event; it needs actual and counterfactual boundaries [Williamson] |
| Full Idea: A river is not just an event. One would need to specify counterfactual as well as actual boundaries. | |
| From: Timothy Williamson (Vagueness [1994], 9.3) | |
| A reaction: In other words the same river can change its course a bit, but it can't head off in the opposite direction. |