When A. J. Ayer commented on Russell’s theory of acquaintance, he claimed that the person who is acquainted with an object knows that the object exists and also that the object in question has the properties which it appears to have. This essay employs Russell’s theory of knowledge by acquaintance from the period between 1910 and 1918 and critically analyzes both the existential and the descriptive statements as they are related to the object of acquaintance. In particular, Ayer’s views on the relationship between appearance and reality are treated as unacceptable from any sound epistemological point of view. I believe that the logical analysis of these epistemological problems reveals intricate issues involved in such discussions, which transcend their limited historical context.