Illustrator Crashes using Pathfinder

After you first install Illustrator on MacOSX you may be faced with the problem of Illustrator crashing without warning. This usually occurs when Illustrator is performing complex actions such as in the Pathfinder. There is a solution to this problem, which I found on the Adobe support page. Follow this routine and your problem should be solved:

Run Illustrator.
Close the Appearance palette.
Quit Illustrator.
Run Illustrator again.

And now when you run Illustrator it should be fixed, and you can now use pathfinder to your liking. The Adobe support page does not explain what the problem is, but it seems to be a software bug related to the Appearance palette and perhaps Intel based Macs. However you should not be afraid of using the appearance palette, because after your crashing problem is fixed for the first time, you can open up your appearance palette again and use it as you normally would.