display all the ideas for this combination of texts
7 ideas
24045 | Movement is spatial, alteration, withering or growth [Aristotle] |
Full Idea: There a four sorts of movement - spatial movement, alteration, withering and growth. | |
From: Aristotle (De Anima [c.329 BCE], 406a12) | |
A reaction: Large parts of Aristotle's writings attempt to explain these four. |
1738 | Practical reason is based on desire, so desire must be the ultimate producer of movement [Aristotle] |
Full Idea: There seem to be two producers of movement, either desire or practical intellect, but practical reason begins in desire. | |
From: Aristotle (De Anima [c.329 BCE], 433a16) |
24044 | Movement can be intrinsic (like a ship) or relative (like its sailors) [Aristotle] |
Full Idea: It is not necessary for what moves things to be itself moving. For a thing can be moving in two ways - with reference to something else, or intrinsically. A ship is moving intrinsically, but sailors move because they are in something that is moving. | |
From: Aristotle (De Anima [c.329 BCE], 406a03) | |
A reaction: I love the way that Aristotle is desperate to explain the puzzle of movement, yet we just take it for granted. Very illuminating about puzzles. Newton's First Law of Motion. |
1739 | If all movement is either pushing or pulling, there must be a still point in between where it all starts [Aristotle] |
Full Idea: Every movement being either a push or a pull, there must be a still point as with the circle, and this will be the point of departure for the movement. | |
From: Aristotle (De Anima [c.329 BCE], 433b26) |
24064 | If something is pushed, it pushes back [Aristotle] |
Full Idea: What has pushed something else makes the latter push as well. | |
From: Aristotle (De Anima [c.329 BCE], 435b30) | |
A reaction: Aristotle seems to have spotted that this is intrinsic to massive bodies, and is not just friction etc. Newton adds a vector to Aristotle's insight. |
21202 | The strong force has a considerably greater range than the weak force [Martin,BR] |
Full Idea: The strong nuclear force has a range of 10^-15 m, considerably larger than the range of the weak force. | |
From: Brian R. Martin (Particle Physics [2011], 01) | |
A reaction: This is because the bosons transmitting the weak force (W+, W-, W°) are much heavier than the gluons of the strong force. |
21211 | If an expected reaction does not occur, that implies a conservation law [Martin,BR] |
Full Idea: If some reaction is not observed when there is apparently nothing to prevent it occurring, it is an indication that a conservation law is in operation. | |
From: Brian R. Martin (Particle Physics [2011], 07) |