Human memory is often conceived as involving two
distinct systems: episodic and semantic (e.g. Ref. 1).
Tulving describes episodic memory as the system
that allows us to remember personally experienced
events, and to travel backwards in time to
re-experience those events2. By contrast, semantic
memory is broadly defined as our ‘knowledge of the
world’2. With respect to memories related to the self,
for example, the episodic/semantic distinction would
be captured by the difference between ‘knowing’ the
name of the high school I attended (semantic
memory) versus ‘remembering’ a specific episode,
for example a humiliating social situation, that
occurred while attending the school (episodic
memory) (i.e. ‘know’ versus ‘remember’
judgments3,4). Given that there exists a clear
distinction between these two forms of thinking
about the past, it is puzzling that an analogous
distinction has never been