成功辨识的关键是找到一个足够灵活的模型结构，以捕捉系统的基本特征，同时又足够简单，可以从现有数据中估计出来。

The most important part of teaching is to teach what it is to know.

The heart is the household divinity which, discharging its function, nourishes, cherishes, and quickens the whole body.

同一元素的原子在质量和性质上是相同的。

我从失败中学到的比从胜利中学到的更多。