Some philosophers find the traditional, subjective approach to studying the mind outdated and ineffectual. For them, the attempt to describe the sensation of pain or anger, for example, or the awareness that one is aware, has been surpassed by advances in fields such as psychology, neuroscience, and cognitive science. Scientists, they claim, do not concern themselves with how a phenomenon feels from the inside; instead of investigating private evidence perceivable only to a particular individual, scientists pursue hard data—such as the study of how nerves transmit impulses to the brain—which is externally observable and can be described without reference to any particular point of view. With respect to features of the universe such as those investigated by chemistry, biology, and physics, this objective approach has been remarkably successful in yielding knowledge. Why, these philosophers ask, should we suppose the mind to be any different?

But philosophers loyal to subjectivity are not persuaded by appeals to science when such appeals conflict with the data gathered by introspection. Knowledge, they argue, relies on the data of experience, which includes subjective experience. Why should philosophy ally itself with scientists who would reduce the sources of knowledge to only those data that can be discerned objectively?

On the face of it, it seems unlikely that these two approaches to studying the mind could be reconciled. Because philosophy, unlike science, does not progress inexorably toward a single truth, disputes concerning the nature of the mind are bound to continue. But what is particularly distressing about the present debate is that genuine communication between the two sides is virtually impossible. For reasoned discourse to occur, there must be shared assumptions or beliefs. Starting from radically divergent perspectives, subjectivists and objectivists lack a common context in which to consider evidence presented from each other's perspectives.

The situation may be likened to a debate between adherents of different religions about the creation of the universe. While each religion may be confident that its cosmology is firmly grounded in its respective sacred text, there is little hope that conflicts between their competing cosmologies could be resolved by recourse to the texts alone. Only further investigation into the authority of the texts themselves would be sufficient.

What would be required to resolve the debate between the philosophers of mind, then, is an investigation into the authority of their differing perspectives. How rational is it to take scientific description as the ideal way to understand the nature of consciousness? Conversely, how useful is it to rely solely on introspection for one's knowledge about the workings of the mind? Are there alternative ways of gaining such knowledge? In this debate, epistemology—the study of knowledge—may itself lead to the discovery of new forms of knowledge about how the mind works.