Ron Kreshmar wrote:... No justification for "moving" boat? No meaning for the character for 'support' as yielding, moving out of the way?
If the image of a boat is used at all, then really it's a given that the concept involves some kind of yielding, accommodation and at the same time overall stability. Otherwise one doesn't even mention a boat - one might as well talk about a rock, a house, a mightly tree, or at the other end of the spectrum about a feather, or a sheet of fabric, for instance.
By definition, a boat floats and thus always combines qualities of the stable with the unstable. A floating boat is always in motion, either obviously or, even if seeming to be still, very subtly and always with the potential to move more. Firstly it is always responding to changes/movement in the environment around it (movement from below, as the water itself moves, or movement from above, e.g. from the wind or from being pushed mechanically. It is also able to move itself (by being rowed or sailed); while moving under its own power, from A to B, it will continue to respond to movements acting on it externally. And despite all this accommodation and adaption, it will always tend to return automatically to its own stable, centred state and position. Which is not however a rigid, 'dug-in' state!!
What a great image that is for tai chi, as starting point for responding to attacks. It's not all the story, but it's an important part of it.
It's still not "how to get there" instruction. That's what teachers and training partners are for. But it's a fine cross-check for your training results. And in case this all seems overly abstract or artsy-fartsy, I have encountered or learn(ed) from various people in various styles whose bodies do actually behave this way. They don't all feel identical, but they have this quality in common.
Finally, I'm not saying this is the only possible or important quality in defensive tai chi energies. Lu is quite another, but also related, story. Just talking about peng for the time being...
Cheers,
Giles