Q1.
Can we predict these outcomes with 100% certainty?
Answer
No. Each of the three examples — rain today, the hockey result tomorrow, the monthly lucky draw — is a random event. We know the whole list of results that could occur, but not which one will occur.
Why it happens: knowing the list is not the same as knowing the entry. For the lucky draw we can say with certainty that exactly one slip will be pulled out, and that it will be one of the slips in the box. What no amount of thinking will tell us is whose slip. That gap between "what could happen" and "what will happen" is exactly what the word chance names.
What we can do is grade our confidence. The book gives two ways to say it:
- in words — impossible, less likely, equally likely, more likely, certain;
- as a number on a scale from 0 to 1, which is what the rest of the chapter builds.
Notice that two friends can look at the same sky and give different answers — "the sun is bright, so no rain" against "it is very hot, so rain later". Both are reading the same evidence differently. That is a subjective probability, and it is precisely what Section 7.2 replaces with something anyone can check.
Check it yourself: not everything is random. "The next Monday will come after Sunday" can be predicted with 100% certainty, because it follows from how the week is defined, not from chance. Certainty is possible — just not for random events.