Calude starts talking about the volume in honor of Gregory Chaitin's 60th birthday: "Randomness and Complexity from Leibniz to Chaitin". The book is divided in techical contributions, philosophy, and reminiscence essays. Calude mentions that this book is special among the several he edited because it presents original contributions and is as much forward-looking as recollecting the past.

Calude than presents a number of remarkable results produced by Chaitin in the course of his scientific career. He was among the first to connect physics and computation. The original paper on algorithmic information theory already contained such connections, although it was removed from the paper "at the strong request" of one of the referees. He also mentions Chaitin contribution to the development of RISC processor architecture technology.

Next, Calude exposes his contribution to the volume. Computers are having a high impact on the way mathematics is done, and computer systems such as Mathematica now enable mathematics to be done through a mix of Hilbert-like proving schemes and computational experiments. However, this doesn't mean that there is any less rigor in the way mathematics is done. As Chaitin says, it's much harder to convince a computer than a referee. Implementing ideas in a computer also forces practitioners do develop more clear ideas about the work they are doing. And time will come when the checking of mathematical proofs will be done only by machine.

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