I copied this from somewhere long ago...closest I get to a citation.
Professor Tomiki also expressed the ideal state of mind and body in aikido as: "Mushin Mugamae".
According to Professor Tomiki, "mushin" is a state of mind that is free -- that does not dwell in any particular place and is thus everywhere. He once likened it to water; water can follow natural terrains and go everywhere but can at the same time be overwhelming. It is the state of mind that can perceive everything around you; you are ready for anything and everything. [Sometimes, "mushin" is narrowly translated as "no mind" but that does not convey its meaning well.]
The term "mugamae" literary means "no posture" or "no stance". It is to be understood that it will take years of dedicated practice before one can hope to attain this enlightened state. It is proper to enter the practice of aikido through "jigotai" (defensive posture). From that modest beginning, one endeavors to graduate -- through years of training -- to "shizentai" (natural posture), or "mugamae".
It is perhaps easier to grasp the meaning of "mushin mugamae", if one thinks of it as a state of mind and body that one pursues throughout one's life.
Dao De Jing, #64: What is Rooted
16 hours ago