This lecture investigates the philosophical status of objects perceived through the five senses and the linguistic frameworks used to describe them. J.O. Urmson, a prominent British philosopher known for his work in ordinary language philosophy, examines how we categorize sensory data. He challenges traditional philosophical assumptions about the nature of perception by analyzing the relationship between sensory experience and the objects to which those experiences refer.

Experts recognize this lecture as a significant contribution to mid-20th-century analytic philosophy. Readers frequently note the academic density of the prose, which is typical of the Hertz Trust Lecture series.