Re: Aikido and Preserving Ego
I think there are really interesting issues here.
Concerning the reason for self-defense, I also think a good way to look at it is in a broader sense of self. In true unity with your "attacker," self-defense is equally keeping the other person from harm as much as yourself. I also see it a way to prevent bodily harm from oneself but without lowering and injuring yourself by inflicting pain on the other person. I have a more occidental philosophical frame of reference, so I think of it in terms of the Platonic dialogue "Gorgias," in which Socrates argues that it is better to suffer injustice than to inflict on another-- even if the person has already done injustice to you. That is how injurious injustice of any kind (physical or otherwise) is to your soul. Aikido, therefore, allows a third path where you can prevent the other person from doing physical harm to you without reciprocating; while also ideally stop the harm the attacker is doing to his soul by attacking you. In other words, with aikido you can take both your and his negative energy and, by redirecting it, change it into positive energy and a learning experience for both.
I do differ on the question of self-improvement. For me (i.e. making no claims that is univerally true), that is the first preliminary goal of aikido-- to improve oneself and become in harmony within oneself (masakatsu agatsu). Once you're well started on that road, I think you should then extend and harmonize with those around you... and gradually expand your circle (the universe being the goal). But that first step of self-improvement and working on yourself seems to me to be an essential first and foundational step. How successfully can you love and harmonize with others without loving and harmonizing within yourself?