Theory of Probability - Paperbackby Oscar Sheynin (Author) This treatise is written on an elementary level; in more difficult cases the final formulas are provided without proof. Nevertheless, it was impossible to leave out integrals and I also had to differentiate an integral with respect to a parameter. I include many examples taken from the history of probability and hope that my subject has thus become lively. I especially quote Karl Pearson's (1978, p. 1) repentant confession: I