 An example will make this idea clearer. Consider Oscar, who believes that water is wet. This belief involves the concept of water, and arguments like Putnam’s appear to show that the ordinary content of this concept is broad. The proposal we are considering is that there is a more detailed description that captures the narrow content, for Oscar, of the concept of water. This description might be something like “clear, colorless, odorless liquid that falls from the sky and fills the lakes.” Oscar and his Twin may share this descriptive content even though their ‘water’-concepts do not have the same broad content. The suggestion, then, is that, when Oscar thinks the thought that he would express by saying “water is wet,” and when Twin Oscar thinks the thought that he would express by saying, in Twin English, “water is wet,” both of them are expressing a thought with the descriptive content “the clear, colorless, odorless liquid that falls from the sky and fills the lakes is wet.” This narrow content, the proposal continues, determines, on Twin Earth, the broad content that XYZ is wet, while on Earth it determines the broad content that water (i.e. H2O) is wet.