groupdeterminac's comments

You'll sometimes see it like so, written with a capital K

Needing help with one part of this. Say in the simplest case of a coin flip and two instants in time I assess probabilities:

  t=0: P(heads) = 0.75, P(tails) = 0.25
  t=1: P(heads) = 0.60, P(tails) = 0.40

These are consistent (or behave as probabilities or what have you) at each time (separately), so de Finetti's argument covers each (separately). Does this alone somehow protect from arbitrage over time? Or is the martingale stuff in the next paragraph, though postured as only a technical rephrasing, essential? Unsure since that part's over my head.

The above's enough to pose the question, but continuing for concreteness: if a buyer can determine any "significant" pattern in my assessments over time--for instance maybe my past assessments have been routinely seen to tend to a uniform distribution over time--aren't I still vulnerable to arbitrage, or else what's protecting me?

> Importantly, the cycle of thought proceeds one step at a time. The brain’s networks of neurons are highly interconnected, so there seems little scope for assigning different problems to different brain networks. If interconnected neurons are working on entirely different problems, then the signals they pass between them will be hopelessly at cross-purposes—and neither task will be completed successfully: Each neuron has no idea which of the signals it receives are relevant to the problem it is working on, and which are just irrelevant junk. If the brain solves problems through the cooperation computation of vast networks of individually sluggish neurons, then any specific network of neurons can work on just one solution to one problem at a time.

Are we to conclude upon observing the crossing paths of trains and passengers that a rail system can service only one route at any moment?