A conceptual integration and review are presented of three separate research programmes informed by the theory of lay epistemics (Kruglanski, 1989). They respectively address the owhyo, ohowo, and owhoo questions about human knowledge formation. The owhyo question is treated in work on the need for cognitive closure that propels epistemic behaviour and affects individual, interpersonal, and group phenomena. The ohowo question is addressed in work on the unimodel (Kruglanski, Pierro, Mannetti, Erb, Chun, 2007) depicting the process of drawing conclusions from the oinformation giveno. The owhoo question is addressed in work on oepistemic authorityo highlighting the centrality of source effects (including oneself as a source) in human epistemi...