It's definitely worth a look! Richard O'Keefe, one of the most highly regarded and accomplished Prolog programmers, even wrote his own Smalltalk implementation

It's definitely worth a look! Richard O'Keefe, one of the most highly regarded and accomplished Prolog programmers, even wrote his own Smalltalk implementation too: http://www.cs.otago.ac.nz/staffpriv/ok/software.htm http://www.cs.otago.ac.nz/staffpriv/ok/software.htm