We had indicated earlier the whole of chapter 3 of the course textbook as reading on uncertainty, etc. We will, however, only use the first part until p. 62, middle.
You should take a look also at the remaining part of the chapter, but consider it as background reading and (perhaps) motivation to search for more literature in case you may have a further interest in the topics.
Unfortunately this second part of the chapter is highly problematic, both concerned with the presentation and the technical quality, and we cannot recommend it. So do not despair if you got stuck in trying to understand it.
We will prepare an example and exercise to make the definitions of section 3.2 more clear, and provide some notes on the application of Bayes' theorem for classification based on statistics which also can be seen as a standard application of machine learning. Other applications are under consideration.