While the three states are:
- waking, experienced by vishva, represented by a,
- dreaming, experienced by taijasa, represented by u and,
- sleeping, experienced by prajna, represented by m,
When one looks at understanding turIya, it is still turIya. But once *in* turIya, none of the three states exist; in which case, usage of the term turIya is rendered meaningless. Then, all thats left is the state that was earlier termed as turIya; thats the state when no individuality of soul(s) remain(s) and there's only aikya... ekameva advitIya brahmaN..., considered beyond the fourth: turIyAtIta.