Trying to get a gem working so, following a SO suggestion, I deleted older versions of ruby I had as follows:

```
$ which -a ruby
/Users/snowcrash/.rvm/rubies/ruby-1.9.2-p318/bin/ruby
/Users/snowcrash/.rvm/bin/ruby
$ rm /Users/snowcrash/.rvm/bin/ruby

```

However, a couple of hours later I tried `which -a ruby` again and this file had returned:

```
/Users/snowcrash/.rvm/bin/ruby

```

Any suggestions how that happened?

Running Mac OS X 10.8.2.