[1] Following the completion of a PhD in astrophysics in 1994, Lepeltier taught in Newcastle, Toulouse, and Paris,[2] he focused his research on the history and philosophy of science.
[3] He later discovered animal ethics and developed an interest in veganism after reading Charles Patterson's Eternal Treblinka.
[10][11] Lepeltier is also the author of several works attempting to deconstruct the discourses justifying the use of animals, he mobilizes on these occasions a wide variety of arguments from the three major currents of normative ethics, whether it is a question of recalling the definition of speciesism according to Peter Singer,[11] that the theories of the social contract do not impose (like babies) to be able to respect duties in order to have rights,[11] or that it is cruel to deprive animals of their lives for the personal pleasure gained by eating them.
[12] He has sometimes been criticised for his condemnation of all breeding (without distinction between industrial and non-industrial varieties) and his use of analogies with human slavery or The Holocaust.
[9][16] Lepeltier has distinguished himself within the French animalist movement, as a defender of interventionism in favor of reducing the suffering of wild animals.