The Concept “The Moon” Is Not a Concept
Ontological Saturation.—One way in which a concept can be considered narrow would be because only one (or a few) objects fall under its extension. This is the case of “natural satellite of the Earth”—an example employed by Frege. This example, however, isn’t necessarily narrow in the sense of having a narrow extension; it is in another sense a highly general concept because it is a special case of the very general concept of a moon. If, at some future date, the solar system is flooded with many asteroids, say, from some extraterrestrial close encounter, the Earth could acquire many additional natural satellites, and then the concept “natural satellite of Earth” could have a great many objects fall under its extension. The fact that this concept can have a changing extension reflects a generality compatible with its current narrowness. The conceptual simplicity of “natural satellite of Earth” betrays its generality, even if a single object, or no object at all, falls under the concept; in this case, the intension is simple, and that simplicity can yield a narrow or a wide extension. A complex intension more readily yields a narrow extension, and an intension might be narrow in more than one way, but that is because there are an infinitude of forms of particularism that could render an intension narrow. We can arrive at particularism by specifying many properties (restricting the extension by expanding the intension) or through the use of highly particularistic concepts, but highly particularistic concepts are naturally complex, i.e., they tacitly incorporate a greater complexity of intension. The concept “natural satellite of Earth” can be made less complex by eliminating the qualifier “natural” and by substituting any planet for “Earth,” but it can also be made more complex by specifying the diameter or orbital distance or even surface features of the natural satellite. When we think of “The Moon” in all is particularity we could be said to entertain the concept of the Moon, but this is misleading, like Hegel’s “concrete universal,” which isn’t a concept at all. A concept is, as Frege noted, “unsaturated,” but any concrete individual is particular in virtue of its ontological saturation.

















