Sources

I thought that some events happen again and again in our daily life. Sir Newton, however, has told us only three sources. If he had survived he might have gone on to speak of many more sources

For example, on the telephone, when you do something wrong

Work formula: The tip of your nose will itch when your hand is filled with ink while working.

Line formula: When you leave one line to go faster and stand in another line, the left line will move faster than the line you are standing on.