I showed Te Kooti's letter to a Maori friend of mine, and she said Te Kooti is ‘porangi’ (crazy).
Synonyms
severely mentally ill, mentally ill, insane, mad, certifiable, deranged, demented, of unsound mind, out of one's mind, not in one's right mind, not together, crazed, maniac, maniacal, lunatic, unbalanced, unhinged, unstable, disturbed, distracted, stark mad, manic, frenzied, raving, distraught, frantic, hysterical, delirious, mad as a hatter, mad as a march hare