In recent years the topic of consciousness has gained some credibility as a serious research issue, at least in philosophy and neuroscience, e.g., [9]. However, there is a lack of technical justifications of consciousness: so far nobody has shown that consciousness is really useful for solving problems, although problem solving is considered of central importance in philosophy [31].
The fully self-referential Gödel machine may be viewed as providing just such a technical justification. It is ``conscious'' or ``self-aware'' in the sense that its entire behavior is open to self-introspection, and modifiable. It may `step outside of itself' [14] by executing self-changes that are provably good, where the proof searcher itself is subject to analysis and change through the proof techniques it tests. And this type of total self-reference is precisely the reason for its optimality as a problem solver, in the sense of Theorem 4.1.