Peter Singer, the author, is a constant voice throughout the work. As not only the narrator who leads the reader through the realities of animal experimentation and “factory farming,” but also the challenger of commonly held beliefs and the inciter of original thoughts concerning “speciesism,” Singer’s characterization is vital to the persuasiveness of his argument. Throughout the work, Singer openly acknowledges the radical and controversial nature of his comparisons of “speciesism” to racism and sexism. His acknowledgement allows him to earn the reader’s trust, just as his decision to include quotes and statistics directly from the scientists and food corporations responsible for animal experiments and “factory farming” does.