What you say makes sense, as usual =], but I'm afraid I'm still having trouble thinking of specific examples where it would be better. You mention several fields such as AI and so forth, but the example you gave doesn't seem like that much of a win over an imperative language, unless I'm drastically missunderstanding it. Here is my interpretation of your prolog: 
sub is_average {
  my $self = shift;
  if( not $self->foreigner and not $self->spouse and $self->income > 3
+000 )
  {
    return 1;
  }
}

[download]
Although I'm not sure where Income2 really enters in to it, perhaps my $self->income should return a list of incomes, but that's a minor detail, yes?

In reply to Re^5: (why to use logic programming) by BUU
in thread Easy Text Adventures in Perl by Ovid

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