A Popperian Platform for Programming and Teaching the Global Brain

Speaker: Karl Lieberherr, College of Computer and Information Science, PRL, Northeastern University, Boston, Massachusetts.

The talk will be on June 21st, 2012, at 4pm at the University of Zurich, Department of Informatics in room 2.A.01. How to reach us.


In a recent article in the Communications of the ACM (May 2012) on Programming the Global Brain, Bernstein et al. make the point that developers of global brain systems need to be societal engineers coordinating societies of many diverse workers. Bederson et al. (2011) address the "remote person call" issue of global brain systems which is about exploitation and ethics issues. Over the last five years we have been experimenting with the Scientific Community Game (SCG) that tries to foster innovation in technological domains through good societal engineering but also learning so that workers benefit from the interaction with requesters and other workers (reducing exploitation, workers become both students and teachers). In the terminology of Bernstein et al., SCG is a constraint-based programming platform parameterized by playgrounds that define the detailed constraints for a domain.

In the SCG we build knowledge bases of claims that are defended by members of the community against attackers. We use a critical rationalism (= Popperian) approach where each claim is disputable. The refutation protocol, in its simplest form, is: If you produce an x in X and I produce a y in Y, property p(x,y) holds. The successful defenders of claims have good technological know-how (for the given playground and relative to the quality of the other workers). It is this technological know-how which is of interest to the requesters and it is transfered to them as software or heuristic descriptions or by hiring the successful workers.

I will introduce the rules of SCG, its playgrounds that are inhabited by workers or avatars ( produced by workers). Interesting specializations of SCG are the Quantifier Game from logic but also the Renaissance Game from the 16th century. I will report on our successes and failures to create games that produce innovations and learning (I have written a playground designer's guide that helps designers to be good societal engineers). Our most successful instantiation of the Scientific Community Game was through the learning tool piazza.com in an Algorithms class with 35 undergraduates. I have also used SCG successfully to gamify software development for optimization tasks.

Supported by Novartis. Joint work with Ahmed Abdelmeged. SCG-Publications.

Short Speaker Bio

Karl Lieberherr started his research career in computer science as a theoretical computer scientist, focusing on the theory of P-optimal algorithms for the generalized maximum satisfiability problem (MAX-CSP), still an active area of research. This work has motivated the development of a game platform for refutation-based, constructive scientific domains, called the Scientific Community Game (SCG) also known as the Specker Challenge Game, named after former ETH Professor Ernst Specker. He also invented, independently and simultaneously on the other side of the Atlantic (at ETH Zurich), an early form of non-chronological backtracking based on learned clauses (superresolution) which has become a key feature of most state-of-the-art SAT and CSP solvers.

In the mid 1980s, he switched to his current research area: Object-Oriented and Aspect-Oriented Software Development and focused on issues of software design and modularity. He founded the Demeter research team, which studied the then-novel idea of Adaptive Programming, also known as structure-shy programming and produced the Law of Demeter ("talk only to your friends": an explicit form of coupling control) and several systems for separating concerns in an object-oriented and functional programming context: From Demeter/Flavors to DemeterF.

Dr. Lieberherr is a Professor in the College of Computer and Information Science at Northeastern University.