On primary sources of chaos

Nowadays, even respectable writing often relies on secondary sources. One of the most-cited ideas of the current period is that the flapping of a butterfly's/humming-bird's/mosquito's wing in Peru/Brazil/Panama (it's usually South America) can cause a hurricane/typhoon/tornado/flood in the US/Russia/wherever.

Click on the heading link for the primary source, from Ed Lorenz (1917-2008), and get the answers right next time you use it.

But thanks too for the secondary source which put me on to this (the full link will break the layout).