What is zen to you that you felt?
Hard to describe without context, but zen is part of all things, including how we present ourselves, how we interact, peacefully or with force, how we rest, where we get our internal strength from and how we give out that energy. Zen flows through all things from martial arts to calligraphy to making tea ...
The result of practiced transcendental meditation left me in a state of mushin, the depth of which I have been unable to reach otherwise. The mind without mind, as it's called; a clarity of thought and vision, absolutely unhindered by conscious thought, or doubt, or almost ... awareness. It was akin to the sort of flying sensation runners can get when their mind and body click and they just run; breathing almost irrelevant, it's just happening exactly as it should be. I get to that state during Epee Fencing and know that's the clicker to push on to fudoshin ... in essence, what will be will be.
You've seen The Matrix, right? Neo is shoshin, willing to learn and wanting to progress. He does. He becomes mushin, where he can see the matrix and clicks into it. That's mushin. He achieves fudoshin at the end, when it almost doesn't matter what he does because it will ... well, it will be.
Some might call it an element of instinct, and there is a certain giving in to primal instinct, unlearning convention. Instinct is learned, by repetitiion. A good swordsman or archer can only pull off such instinctual actions having practiced and practiced and practiced ... that is not fudoshin, but I don't think fudoshin can be achieved without.
Bruce Lee talked about "flow like water" ... water has a life and a purpose, but it will flow where it flows. Fudoshin. Anyway, mushin is about a crystal clear mind. Absolutely devoid of anything that detracts from its purity. Transcendental meditation got me to a purity that I have not experienced in any other way ... but boy, the headaches afterwards were not fun.
Sheesh! That's not a bad impression of someone who knows what they're talking about ... impression of ... I really don't. I've dabbled, but I do practice elements of zen with my fencing, and it does reap benefits ... not just for the fencing, but for my life generally.
Still searching for satori ... the kick in the eye.