content, wide and narrow

What a person expresses by a sentence is often a function of the environment in which he or she is placed. For example, the disease I refer to by a term like ‘arthritis’ or the kind of tree I refer to as a ‘beech’ will be defined by criteria of which I know next to nothing. This raises the possibility of imagining two persons in rather different environments, but in which everything appears the same to each of them (see twin-earth ). The wide content of their thoughts and sayings will be different if the situation surrounding them is appropriately different: ‘situation’ may here include the actual objects they perceive, or the chemical or physical kinds of object in the world they inhabit, or the history of their words, or the decisions of authorities on what counts as an example of one of the terms they use. The narrow content is that part of their thought which remains identical, through the identity of the way things appear, regardless of these differences of surroundings. Partisans of wide (sometimes called broad) content may doubt whether any content is in this sense narrow; partisans of narrow content believe that it is the fundamental notion, with wide content being explicable in terms of narrow content plus context.