Abstract: Argues for the thesis of universal ignorance, i.e., for the claim that nobody can ever know anything. To this effect, puts forward versions of the classical Cartesian argument for skepticism as well as novel arguments involving normative premises and the concept of certainty. Universal ignorance gives rise to further skeptical results: in order to be justified or reasonable in believing something, the subject must know something to be so. Likewise, many attitudes (e.g., being happy about or regretting something) and “illocutionary acts” (e.g., commanding, apologizing) require that the subject knows something. Since nobody can ever know anything, it follows that nobody can ever be justified or reasonable in believing anything, that nobody can ever be happy about or regret anything, and that nobody can ever command or apologize for anything. Finally, the book argues that not only is knowledge impossible, but so is truth. The remedy it suggests is a radical change in our language.

Keywords: certainty, ignorance, illocutionary acts, justification, knowledge, language, normativity, rationality, skepticism, truth