What Is Episodic Memory?

Few problems In science are as difficult as those of working out the precise relation between two compiex concepts that are deceptively similar. The relation between episodic and semantic memory belongs in this category. Intuition and rational thought reveal many similarities between these two kinds of memory and tempt us to think of the two as one. Yet, closer scrutiny reveals a number of fundamental differences. In this article, I discuss one such difference, namely, the nature of conscious awareness that characterizes retrieval of episodic and semantic information. Not everyone accepts the general idea of multiple memory systems, and among those who do, not everyone accepts the same scheme of classification. ^ What follows represents my views on the issue. The distinction between episodic and semantic memory has changed considerably since my 1972 essay In which I argued for the heuristic usefulness of a taxonomic distinction between episodic and semantic memory, conceived of as parallel, partially overlapping information processing systems. At that time, I could think of only five (hypothetical) differences between the two kinds of memory. Some 10 years later, in 1983, ! suggested that, de-