How should we account for our ability to entertain simple, vision-based demonstrative thoughts about particular objects (that is, our ability to entertain thoughts about particular objects simply on the basis of seeing them)? In this thesis I propose an account of this ability that accords with the common-sense view that seeing an object puts one in a position to single it out by visually attending to it, and that this provides one with the ability to entertain demonstrative thoughts about it. An account of this type requires that we account for what it is to see a particular object and to visually attend to it without appealing to particular demonstrative abilities. However, it has been argued that a notion of seeing an object, and similarly a notion of attending to an object, which is accounted for in this way is unsuitable for accounting for demonstrative abilities. I argue that there is no real problem: what we need is a notion of experiential content which is concept-dependent only in a general manner. That is, the account of the relevant notion of experiential content requires appeal to the subject's conceptual abilities, but the account is not given in terms of specific conceptual abilities (especially, not specific demonstrative abilities). I then characterize a notion of attention to a seen object which can be accounted for without appeal to particular demonstrative abilities, and explain how attending to an object in the relevant sense provides the subject with the ability to think about the object demonstratively. It is widely agreed that spatial location plays a central role in an account of demonstratives. I explain this role in terms of the role played by location in visual attention to the object and the subject's grasp of the fact that he attends to the object.