▁of ▁wonder ment , ▁eng ross ment ▁and ▁confusion ▁are , ▁in ▁fact , ▁just ▁kinds ▁of ▁tr ance . ▁ ▁Clear ly , ▁there ▁are ▁a ▁great ▁many ▁kinds ▁of ▁tr ance . ▁Many ▁people ▁are ▁familiar ▁with ▁the ▁idea ▁of ▁a ▁" deep " ▁tr ance , ▁and ▁earlier ▁in ▁his ▁career ▁Er ick son ▁was ▁a ▁pione er ▁in ▁research ing ▁the ▁unique ▁and ▁remarkable ▁phen omena ▁that ▁are ▁associated ▁with ▁that ▁state , ▁sp ending ▁many ▁hours ▁at ▁a ▁time ▁with ▁individual ▁test ▁subjects , ▁deep ening ▁the ▁tr ance . ▁ ▁That ▁a ▁tr ance ▁may ▁be ▁" light " ▁or ▁" deep " ▁suggests ▁a ▁one - dimensional ▁continu um ▁of ▁tr ance ▁depth , ▁but ▁Er ick son ▁would ▁often ▁work ▁with ▁multiple ▁tr ances ▁in ▁the ▁same ▁patient , ▁for ▁example , ▁suggesting ▁that ▁the ▁hyp not ised ▁patient ▁behave ▁" as ▁if ▁aw ake ", ▁thereby ▁bl urr ing ▁the ▁line ▁between ▁the ▁hyp not ic ▁and ▁aw ake ▁state . ▁ ▁Er ick son ▁believed ▁there ▁are ▁multiple ▁states ▁that ▁may ▁be ▁util ized . ▁This ▁reson ates ▁with ▁Charles ▁T art ' s ▁idea ▁( put ▁forward ▁in ▁the ▁book ▁W aking ▁Up ) ▁that ▁all ▁states ▁of ▁conscious ness ▁are ▁tr ances ▁and ▁that ▁what ▁we ▁call ▁" normal " ▁w aking ▁conscious ness ▁is ▁just ▁a ▁" cons ensus ▁tr ance ". ▁N LP ▁also ▁makes ▁central ▁use ▁of ▁the ▁idea ▁of ▁changing ▁state , ▁without ▁it ▁explicitly ▁being ▁a