A business man once stated that there is nothing so practical as a good theory.

See how today's achievement is only tomorrow's confusion; See how possession always cheapens the thing that was precious.

"But in theory…"
"When we are dealing with history, theories are worthless," Doniger said with a contemptuous wave. "A theory is only valuable if it has the ability to predict future outcomes. But history is the record of human action—and no theory can predict human action."

Then he decided that nothing was more impractical than misplaced practicality.

experience is comparable to fashion; an action that proved successful today will be unworkable and impractical tomorrow. Only principles endure

Every today is at the same time both a cradle and a shroud: a shroud for yesterday, a cradle for tomorrow. Today, yesterday, and tomorrow are equally near to one another, and equally far. They are generations, they are grandfathers, fathers, and grandsons. And grandsons invariably love and hate the fathers; the fathers invariably hate and love the grandfathers. Today is doomed to die — because yesterday died, and because tomorrow will be born. Such is the wise and cruel law. Cruel, because it condemns to eternal dissatisfaction those who already today see the distant peaks of tomorrow; wise, because eternal dissatisfaction is the only pledge of eternal movement forward, eternal creation. He who has found his ideal today is, like Lot's wife, already turned to a pillar of salt, has already sunk into the earth and does not move ahead. The world is kept alive only by heretics: the heretic Christ, the heretic Copernicus, the heretic Tolstoy. Our symbol of faith is heresy: tomorrow is an inevitable heresy of today, which has turned into a pillar of salt, and to yesterday, which has scattered to dust. Today denies yesterday, but is a denial of denial tomorrow. This is the constant dialectic path which in a grandiose parabola sweeps the world into infinity. Yesterday, the thesis; today, the antithesis, and tomorrow, the synthesis.

A great many things are possible.” And to himself he added: But not practical.

The young were always theoretical; only the middle-aged could realise the deadliness of principles. (Ch. 21)

The tricks of today are the truths of tomorrow.

"A great many things are possible." And to himself he added: But not practical.

If tomorrow were never to come, it would not be worth living today.

I am a theorist, but I detest the introduction of abstract principles into the great practical difficulties of this nation.

Nothing can be more idle than the opposition of theory to practice!

Today is all we have, tomorrow is a mirage that may never become reality.