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27. Natural Reality / D. Time / 2. Passage of Time / g. Time's arrow

[that time seems to have one fixed direction]

24 ideas
Newtonian mechanics does not distinguish negative from positive values of time [Newton, by Coveney/Highfield]
When one element contains the grounds of the other, the first one is prior in time [Leibniz]
The direction of time is grounded in the direction of causation [Reichenbach, by Ladyman/Ross]
An ordered series can be undirected, but time favours moving from earlier to later [Le Poidevin]
If time's arrow is causal, how can there be non-simultaneous events that are causally unconnected? [Le Poidevin]
Time's arrow is not causal if there is no temporal gap between cause and effect [Le Poidevin]
If time's arrow is psychological then different minds can impose different orders on events [Le Poidevin]
There are Thermodynamic, Psychological and Causal arrows of time [Le Poidevin]
Presumably if time's arrow is thermodynamic then time ends when entropy is complete [Le Poidevin]
If time is thermodynamic then entropy is necessary - but the theory says it is probable [Le Poidevin]
We must explain either the existence of a time direction, or our psychological sense of it [Price,H]
Causation is the power of one property to produce another, and this gives time its direction [Esfeld]
We judge memories to be of the past because the events cause the memories [Bardon]
To define time's arrow by causation, we need a timeless definition of causation [Bardon]
The psychological arrow of time is the direction from our memories to our anticipations [Bardon]
The direction of entropy is probabilistic, not necessary, so cannot be identical to time's arrow [Bardon]
It is arbitrary to reverse time in a more orderly universe, but not in a sub-system of it [Bardon]
Entropy is puzzling, so we may need to build new laws which include time directionality [New Sci.]
Only heat distinguishes past from future [Rovelli]
Static theories cannot account for time's obvious asymmetry, so time must be dynamic [Baron/Miller]
The direction of time is either primitive, or reducible to something else [Baron/Miller]
The kaon does not seem to be time-reversal invariant, unlike the rest of nature [Baron/Miller]
Maybe the past is just the direction of decreasing entropy [Baron/Miller]
We could explain time's direction by causation: past is the direction of causes, future of effects [Baron/Miller]