The ten stems split each element into a yang and a yin form, and 甲 is the yang face of wood — not stronger wood, but wood used for timber: one trunk, growing straight, taller than anything else given time, at the cost of not being able to bend.
You'll recognise it here: you take on structural roles without being asked; you find it hard to swallow 'just do it this way for now'; and you need a visible long direction — without one, your force has nowhere to exit and you get restless.
Running well, 甲 is the trunk holding the whole thing up: with you there, the frame doesn't fall. Blocked, it goes two ways. One is hardness — going at something you know won't give, because admitting a detour is harder for you than the wall. The other is being spent on small things: the trunk split into a hundred branches, visibly busy, none of them tall. So 甲's practical lesson isn't softening. It's picking something big enough — with a large enough container you stop needing to fight over the small ones.
