The spinozian critical fortune records that, starting withproposition 27 of Ethics Part iii, something completely original appearsin the examination of affective life: the imitation of affections. Spinoza’snovelty, in comparison with his contemporaries, is to describe theproduction of affections no longer from an external object, but from theconduct of “something”, or “someone”, on an object - considering thatthis production is rooted in the fact that we imagine that this “someone”or that “something” is similar to us. The proposition links a longdeductive sequence (...) that runs through the rest of Part iii, supports thecrucial Part iv propositions on politics and law and reaches the PoliticalTreaty [i, v]. Our intention is to evaluate the meanings of this propositionin Spinoza’s political thought, based on a review of this problemin critical fortune - taking into account some passages in the works ofPrimo Levi. In particular the “Chemistry Test”, chapter ofthis book If This Is a Man? [Se questo è un uomo?]. (shrink)