In this paper, unconventional logic for massive-parallel reasoning is introduced and two examples of simulating natural processes by means of this logic are regarded: chemical (Belousov-Zhabotinsky reaction) and biological (dynamics of plasmodium of Physarum polycephalum). In unconventional logic well-formed formulas are defined as streams and there are possible so-called wave sets of formulas (where all members are non-well-founded). This way of simulating is much simpler in applications of unconventional computing than sequential thinking.