You can draw a line in the sand: the final sanction, the ultimatum. You can make castles from it: fanciful and free. In your eyes, sand is bad, and to build a house upon it, pure folly. The sands run through the hourglass, get in your eye and the feel of it under your feet is a metaphor for freedom and happiness. Quicksand can swallow you up, as, in time, it will swallow the pyramids, reduced to sand and dust.
Nothing has permanence: not structure or law, idea or life. In time, all things come to pass. The line we draw in the sand today is eroded by wind, by the action of waves, by the passing feet of children. The great edifices of power are ground down slowly, one abraded grain at a time: nothing can resist that corrosive power. Great ideas are humbled by the intractable action of time over matter. Those things we hold true, those facts that are immutable: all humbled by the the sand in the wind, the constant abrasion and touch. Permanence is the illusion, made real by perspective, but thwarted one grain at a time. Because the lesson we learn is that nothing is forever, not idea or notion, premise or belief. To learn is to change, to be tumbled by new ideas and thoughts as grains of sand roll along the beach.
Words about learning is an occasional series of posts reflecting on aspects of learning in a more poetic style.