Old paint on canvas, as it ages, sometimes becomes transparent. When that happens it is possible, in some pictures, to see the original lines: a tree will show through a woman's dress, a child makes way for a dog, a large boat is no longer on an open sea. That is called pentimento because the painter 'repented,' changed his mind. Perhaps it would be as well to say that the old conception, replaced by a later choice, is a way of seeing and then seeing again.

It's perhaps easier now than ever before to make a good living. It's perhaps harder than ever before to stay calm, to be free of career anxiety. I want to look now, if I may, at some of the reasons why we might be feeling anxiety about our careers. Why we might be victims of these career crises, as we're weeping softly into our pillows. One of the reasons why we might be suffering is that we are surrounded by snobs.

篮球是一项容易学习但难以精通的运动。

论证是一种颓废的意志

嗷，好高兴你来了，我有一百件事不想告诉你。

In the world of mathematics, imagination is more important than knowledge.