The reversibility of Prolog computations was a big eye opener for me too back when I first encountered it. I recently wrote a post about relational programming

The reversibility of Prolog computations was a big eye opener for me too back when I first encountered it. I recently wrote a post about relational programming using Prolog and Mozart/Oz as examples https://bluishcoder.co.nz/2017/03/20/relational-programming-in-mozart-oz.html https://bluishcoder.co.nz/2017/03/20/relational-programming-... Another interesting language in the same domain is Picat http://picat-lang.org/ http://picat-lang.org/