温老（Steven Weinberg）为新书To Explain the World: The Discovery of Modern Science (HarperCollins, 2015)写了一个尾声，“宏大的还原”（Epilog: The Grand Reduction），大概将科学史概括为还原的历史——他的还原观是说科学解释向着一点汇聚（在他看来，粒子物理学距离那点最近）。

最后一段话有点儿意思，是“即兴重复”《物种起源》的最后一段（a riff on the last paragraph of Darwin’s Origin of Species），也可以说是一句话的科学史：

This is a grand story, how celestial and terrestrial physics were unified by Newton, how a unified theory of electricity and magnetism was developed that turned out to explain light, how the quantum theory of electromagnetism was expanded to include also the weak and strong nuclear forces, and how chemistry and even biology were brought into a unified though incomplete view of nature based on physics. It is toward a more fundamental physical theory that the wide ranging scientific principles we discover have been, and are being, reduced.

达尔文的原话是（如此的科学文字真心好味道啊）：

There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

两段文字相通的地方，都是为自然律感到欢欣鼓舞。达翁看见从一个简单的开始生出万千生命，温老则看见天下万物的科学原理将复归于（reduced toward）一个更基本的物理学理论。不管我们怎么看物理学和生物学的进化，这种对自然律的态度和眼光，都是应该发扬光大的。