In MN 72 we find the rather obscure term mathita. Ven Bodhi, followed by Ven Thanissaro, has “excogitations”, which, apart from being obscure, has the wrong sense:
To consider or think (something) out carefully and thoroughly.
Horner has “supposing”, apparently taking it as a straight synonym for maññati, with which it occurs in parallel. The dictionaries are not hugely helpful.
But at Thag 14.2 we have:
Yathāpi bhaddo ājañño,
Just as a fine thoroughbred,
dhure yutto dhurassaho;
Yoked to a carriage, endures the load,
Oppressed by the heavy burden,
Here it clearly means “oppressed, weighed down”, and the same sense probably applies at Thag 1.102, too.
So in a psychological sense it would be “burdens, anxieties, worries”. The passage would then read:
Tasmā tathāgato sabbamaññitānaṃ sabbamathitānaṃ sabbaahaṅkāramamaṅkāramānānusayānaṃ khayā virāgā nirodhā cāgā paṭinissaggā anupādā vimuttoti vadāmi
That’s why the Realized One is freed with the ending, fading away, cessation, giving up, and letting go of all conceivings, all worries, and all ego, possessiveness, or tendency to conceit, I say.