Thinking on the Web: Berners-Lee, Gödel and Turing

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BERNERS-LEE: WHAT IS SOLVABLE?

OVERVIEW

When Tim Berners-Lee was developing the key elements of the World Wide Web, he showed great insight in providing HTML as a simple easy-to-use Web development language. As a result, it was rapidly and widely adopted. To produce Web information required skills that could be learned with a high-school-level education. Consequently, personal computing merged with global networking to produce the World Wide Web.

The continuing evolution of the Web into a resource with intelligent features, however, presents many new challenges. The solution of the World Wide Web Consortium (W3C) is to provide a new Web architecture that uses additional layers of markup languages that can directly apply logic. However, the addition of ontologies, logic, and rule systems for markup languages means consideration of extremely difficult mathematic and logic consequences such as paradox, recursion, undecidability, and computational complexity on a global scale. Therefore it is important to find the correct balance between achieving powerful reasoning with reasonable complexity on the Web.¹ This balance will determine what is solvable on the Web in terms of application logic.

In this chapter, we briefly review Berners-Lee’s contribution in developing the Web. Then we look at the impact of adding formal logic to Web architecture and present the new markup languages leading to the future Web architecture: the Semantic Web. We conclude with a presentation of complexity ...