1 Introduction

1.1 The problem

In ancient Greek and Roman dramas, when it seemed the characters in the play had no way out, they could be saved through the intervention of a deus ex machina, a god that appeared in the (stage) machinery. In shipping, the opposite sometimes occurs: When everything is running smoothly, a diabolus (devil) ex machina may intervene and cause an accident. When this happens, observers can only wonder where the problem originated. This chapter will analyze computer-based systems to suggest some possible answers to this question and some ways to deal with it in respect of liability law.