A somewhat limited effort to reduce tasks to one another in this vein: http://www.academia.edu/1419272/AI-Complete_AI-Hard_or_AI-Easy_Classification_of_Problems_in_Artificial
A somewhat limited effort to reduce tasks to one another in this vein: http://www.academia.edu/1419272/AI-Complete_AI-Hard_or_AI-Easy_Classification_of_Problems_in_Artificial