Scala Perspective Does Not Show Up in Eclipse - Solution

I just wanted to share a painful lesson so that, hopefully, nobody has to repeat it.

I tried to install Eclipse and the Scala plugin, but after I installed the Scala plugin it wouldn't work. The Scala perspective just didn't show up after the restart. Googling on the problem did not help. It turns out that the problem wasn't with Scala - the problem was that I incorrectly tried to run a 32-bit Eclipse on Mac OS 10.5.8, which is 64-bit. Eclipse will not give an error message of the type "You are trying to run 32-bit software on a 64-bit OS". Things will just randomly stop working with no error messages.