Quick follow up, I need to mention Peter Goldsbury's hugely informative essays including aspects of O Sensei's religious beliefs - what do we need to understand and believe in order to study and progress in Aikido?
Also, from Ellis Amdur's "Hidden in Plain Site":
Ueshiba saw himself as a kind of avatar, instrumental in ushering in a golden age of redemption, the unification of Heaven, Earth, and Man. To a considerable degree, he was unconcerned about whether others became avatars like himself. He regarded aikido practitioners as living out their fate as appointed by their 'chief guardian deity,' doing the work of the "spiritual proletariat," accumulating merit and energy through aikido practice.
For those of us studying Aikido (and related arts) for more than just purely physical aspects, why are we doing what we are doing? What do we accept from our teacher's beliefs and what do we create for ourselves?