We usually think that soft is weak.
But we have heard that soft women when needed can be stronger than most men around them.
Air & water are in gaseous /liquid state , but can erode the rocks in solid state.
Air finds its way into many so called air tight containers.
Water tight compartments are penetrated by water / a leakage by a small lapse.
Water
is fluid, soft, and yielding. But water will wear away rock, which is rigid and
cannot yield. As a rule, whatever is fluid, soft, and yielding will overcome
whatever is rigid and hard. This is another paradox: what is soft is strong