In two studies, students were asked to rate their knowledge of a number of different topics, extracurricular as well as drawn from their textbooks of the history of psychology and philosophy. The score distributions on a scale from “unknown” to “well known” were in all cases distinctly U‐formed, as if knowledge were a question of either/or, rather than one of degree. However, when knowledge was rated on a scale from “know nothing about” to “know much about”, the U‐pattern failed to appear, and the students tended generally to give more cautious ratings. The differences are interpreted as evidence for the philosophical and linguistic distinction between “knowledge by acquaintance” (German: “kennen”, French: “connaître”) and “knowledge‐about