Solid ground, the thing we take for granted until it's gone. Earthquakes show us the dread of floors that give way and of earth that chooses to be liquid for thirty terrible seconds. After months at sea, sailors kiss solid earth; their legs still rocking to imaginary waves.
We say when life spins too fast, when everything seems unstable, "I need solid ground under my feet." We seek assurance, trustworthiness, something not to change when we lean our entire bodyweight against it. Children develop their sense of balance and learn to walk on firm ground, trusting it will not move. Astronauts in zero gravity dream of it, muscles atrophying, bones thinning, longing for weight that means something.
Still, what is solid? Physicists contend it's mostly empty area, with atoms oscillating in formation to produce the convincing illusion of constancy. We all stand on something more empty than material, more consent than truth, trusting that whatever supports us now will also carry us tomorrow.