Aikido Founder Morihei Ueshiba in front of the Shinden in IwamaNote the mitsudomoe design on the drum to his left.
If you haven’t read it yet, I highly recommend that you read Stan Pranin’s article “O-Sensei’s Spiritual Writings: Where did they really come from?” – it’s an important piece, and will lend some background to the rest of this post. Actually, most of this post consists of some thoughts I had after reading that article again.To summarize from Stan Pranin’s article, there are two main sources for post-war materials from Morihei Ueshiba O-Sensei  –  "Takemusu Aiki" and "Aiki Shinzui". The first is the transcription of a series of lectures by O-Sensei for publication in the Byakko Shinko Kai ("White Light Society") newsletter. The second is also composed of transcriptions of lectures given by O-Sensei – this time the transcriptions were done by the Aikikai for publication in the "Aikido Shimbun" newsletters published by Aikikai hombu dojo.