In my mind you cannot be frequentist or Bayesian after reading just the first paragraph of Chapter 2. But fair enough I am a bit too critical here.

Also you are right, set notation does use curly braces, I am relieved :-). I was confused by the A = [-1, 1-1/n] (interval set notation) on page 8 that I misread as [-1, 1, 1/n]...