einstein

So what made Einstein cede the revolutionary road to younger radicals and spin into a defensive crouch?
As a young empiricist, excited by his readings of Ernst Mach, Einstein had been willing to reject any concepts that could not be observed, such
as the ether and absolute time and space and simultaneity. But the success of his general theory convinced him that Mach’s skepticism, even
though it might be useful for weeding out superfluous concepts, did not provide much help in constructing new theories.
“He rides Mach’s poor horse to exhaustion,” Einstein complained to Michele Besso about a paper written by a mutual friend.
“We should not insult Mach’s poor horse,” Besso replied. “Didn’t it make possible the tortuous journey through the relativities? And who knows, in
the case of the nasty quanta, it may also carry Don Quixote de la Einsteina through it all!”
“You know what I think about Mach’s little horse,” Einstein wrote Besso in return. “It cannot give birth to anything living. It can only exterminate
harmful vermin.” 65
In his maturity, Einstein more firmly believed that there was an objective “reality” that existed whether or not we could observe it. The belief in an
external world independent of the person observing it, he repeatedly said, was the basis of all science. 66
In addition, Einstein resisted quantum mechanics because it abandoned strict causality and instead defined reality in terms of indeterminacy,
uncertainty, and probability. A true disciple of Hume would not have been troubled by this. There is no real reason—other than either a metaphysical
faith or a habit ingrained in the mind—to believe that nature must operate with absolute certainty. It is just as reasonable, though perhaps less
satisfying, to believe that some things simply happen by chance. Certainly, there was mounting evidence that on the subatomic level this was the
case.
But for Einstein, this simply did not smell true. The ultimate goal of physics, he repeatedly said, was to discover the laws that strictly determine
causes and effects. “I am very, very reluctant to give up complete causality,” he told Max Born. 67
His faith in determinism and causality reflected that of his favorite religious philosopher, Baruch Spinoza. “He was utterly convinced,” Einstein
wrote of Spinoza, “of the causal dependence of all phenomena, at a time when the success of efforts to achieve a knowledge of the causal
relationship of natural phenomena was still quite modest.” 68 It was a sentence that Einstein could have written about himself, emphasizing the
temporariness implied by the word “still,” after the advent of quantum mechanics.
Like Spinoza, Einstein did not believe in a personal God who interacted with man. But they both believed that a divine design was reflected in the
elegant laws that governed the way the universe worked.
This was not merely some expression of faith. It was a principle that Einstein elevated (as he had the relativity principle) to the level of a postulate,
one that guided him in his work. “When I am judging a theory,” he told his friend Banesh Hoffmann, “I ask myself whether, if I were God, I would have
arranged the world in such a way.”
When he posed that question, there was one possibility that he simply could not believe: that the good Lord would have created beautiful and
subtle rules that determined most of what happened in the universe, while leaving a few things completely to chance. It felt wrong. “If the Lord had
wanted to do that, he would have done it thoroughly, and not kept to a pattern . . . He would have gone the whole hog. In that case, we wouldn’t have
to look for laws at all.” 69
This led to one of Einstein’s most famous quotes, written to Max Born, the friend and physicist who would spar with him over three decades on
this topic. “Quantum mechanics is certainly imposing,” Einstein said. “But an inner voice tells me that it is not yet the real thing. The theory says a lot,
but it does not really bring us any closer to the secrets of the Old One. I, at any rate, am convinced that He does not play dice.” 70
Thus it was that Einstein ended up deciding that quantum mechanics, though it may not be wrong, was at least incomplete. There must be a fuller
explanation of how the universe operates, one that would incorporate both relativity theory and quantum mechanics. In doing so, it would not leave
things to chance.