transpersonal experiences can be defined as ‘experiences involving an expansion or extension of consciousness beyond the usual ego boundaries and beyond the limitations of time and/or space.’
Grof delivers the canonical definition of transpersonal experience as consciousness surpassing ego and spatiotemporal boundaries, and acknowledges the classificatory difficulty posed by the breadth of phenomena this encompasses.
, Realms of the Human Unconscious: Observations from LSD Research, 1975thesis