A major problem within discourse on intentionality is that participants often fail to make explicit whether or not they use the term to imply concepts such as agency or desire, i.e. whether it involves teleology. Dennett (see below) explicitly invokes teleological concepts in the "intentional stance". However, most philosophers use "intentionality" to mean something with no teleological import. Thus, a thought of a chair can be about a chair without any implication of an intention or even a belief relating to the chair. For philosophers of language, what is meant by intentionality is largely an issue of how symbols can have meaning. This lack of clarity may underpin some of the differences of view indicated below.