  This paper is devoted to linear space representations of contextual
probabilities - in generalized Fock space. This gives the possibility to use
the calculus of creation and annihilation operators to express probabilistic
dynamics in the Fock space (in particular, the wide class of classical kinetic
equations). In this way we reproduce the Doi-Peliti formalism. The
context-dependence of probabilities can be quantified with the aid of the
generalized formula of total probability - by the magnitude of the interference
term.
