Abstract
What is the general nature or logical status of existence? This question is the (logically) first question of ontology. Moore, in his early article "The Nature of Judgment", and Russell, in The Principles of Mathematics, offer the same answer to it, and their answer has philosophical—as well as historical—importance. Existence is what Moore calls a "concept" and what Russell calls a "term". The chief features of the early Moore-Russell ontology, their attempt to understand the ultimate constituents of the world and the connections among them, are delineated and evaluated. Though their ontology has its successes (e.g., a useful, univocal concept of existence), it ultimately is a failure, and the reasons for its failure are deeply rooted and instructive.