The things he say can be summed up to a few sentences. In fact, most of the things he talk about can applied to a lot of things in life not just kung fu or wing chun in particular.
One of the things he's talking about is freeing the mind, so that a fighter will respond spontaneously to any situation he comes across. As opposed to a fighter who can only reacts like a robot. That fighter never learn to think for himself, so his art is never truly alive.