Involved

Trinity symbol
(See Sequel.)

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Trinity symbol
by Greg Egan
(via John Baez)

Involved:

 

"Difficult to understand because of intricacy: byzantine, complex, complicated, convoluted, daedal, Daedalian, elaborate, intricate, involute, knotty, labyrinthine, tangled."

— Roget's II: The New Thesaurus, Third Edition

See also the previous three entries,
as well as Symmetries.