"A clever thought usually has many mothers and fathers"


Gottfried Wilhelm Leibniz, researcher, philopsph, gave his name for the Leibniz Supercomputing Centre in Garching. Picture: GWLB

Mathematician, philosopher, inventor, cosmopolitan, today one would add networker: Gottfried Wilhelm Leibniz, who also gave his name to the Leibniz Supercomputing Centre (LRZ) in Garching, lived from 1646 to 1716 and left the world many theories and theorems. Leibniz worked towards the uniformity of scientific terminology; for example, the integral sign, the elongated S as a symbol for "everything" or a sum in mathematics originated from him. In his search for simplification and generalisation, he also developed the foundations for the dual number system, a universal language for mathematics with which all numbers could be represented by the digits 0 and 1 and which is the basis for digital binary codes. The prolific thinker and writer used every half-empty piece of paper to discuss phenomena in nature, mathematical solutions or new techniques. Prof. Dr. Michael Kempe is the master of these pieces of paper and writings, heads the Leibniz Archives in Hanover and is intensively involved with his life and work. In his book "Die beste aller möglichen Welten" (Fischer-Verlag) he condenses the rich work into seven days. In an interview with the LRZ, the historian explains why.

More than 20 biographies and books on Gottfried Wilhelm Leibniz, why another one now? Prof. Dr. Michael Kempe: You can't write enough biographies and books about Leibniz, because there is no single, true perspective on him, and he appears differently in every view. However, Leibniz also complained that too many books were being written. My idea for the book is modest: an introduction to his fascinating world of thoughts and his exciting personality. The book should arouse curiosity and provide access to the Academy Edition of the Leibniz Edition. Not a complete picture, an exemplary approach to keep the communication with him and his thinking alive.

You have been head of the Leibniz Archive since 2011 - has your image of the person changed as a result? Kempe: As the head of the Leibniz Research Centre or the Leibniz Archives, I have a lot to do with administration and easily lose sight of the actual content, i.e. research about and with Leibniz. As a historian, I have learned from Leibniz that administration, science management and the organisation of research data are not a nuisance or a necessary evil. On the contrary: it is part of research, permeates and conditions it, which is what Leibniz's work as an academy founder and science organiser taught me.

Why do you attribute Leibniz's achievements to just seven days of his life? Kempe: Even for an intellectual polyathlete like Leibniz, the day had only 24 hours and the week only seven days. I found it very attractive to show in an exemplary way what Leibniz tackled in one day and also how he kept getting lost, tangled up. The result is a spiral around one of the most stimulating and at the same time most mysterious intellectuals of early modernity.


What can we learn from Leibniz now? Kempe: Never give up, keep trying, don't let yourself be crushed by setbacks and also see something good in bad experiences. You don't need Leibniz to do that, but his attitude as a stand-up guy despite recurring difficulties and the constant threat of failure is, I think, incredibly impressive. Leibniz evokes a disciplined, strangely undercooled optimism that relies on rationality without denying the mercurial chaos of life. Leibniz could also be very emotional at times, but usually returned to an attitude of joyful serenity. I wish I could take a leaf out of his book.

We are on the verge of a new era in computer science: Binary computing is being joined by universal quantum computing. Does the polymath also have theories to offer for this? Kempe: Theories, paradigms and their change have their own logic. Only when a turning point has occurred do we recognise retrospectively what and who all can be considered as precursors. In the 19th century, we already knew Leibniz's binary calculus, which, incidentally, he was neither the first nor the only one to practise. But it was not until around the middle of the 20th century, when digital code began to establish itself as a computer language, that Leibniz could be called one of its initiators. Leibniz's thoughts on combinatorics might not be such a bad idea for a history of ideas on more universal quantum computing. In any case, Leibniz repeatedly tried his hand at it in connection with dyadics, the binary number system, and with reference to the Chinese Yijing oracle. But a clever idea usually has many mothers and fathers, and there is no linear or merely cumulative progress in science. Leibniz showed us to remain modest: What we will know tomorrow, we cannot say today. All we can do is find out what matters. What matters now. The future is, at least partially, contingent, but it can also be shaped.

Who do you particularly recommend your book to? Kempe: Anyone who needs courage for their own everyday life and at the same time likes to dive into foreign, past worlds. Both are to be addressed in the book: the disturbing closeness to a world that we do not count as modern and whose acquaintance makes us forget our own calamities, while we see Leibniz restlessly commuting between the courts of Europe, observe him in the wild whirl of his graphomaniac creation of ever new worlds out of paper and ink. Watching and realising that behind the allonge wig and baroque frock coat, a man emerges who is closer to our concerns and challenges than we would have suspected. For those who want to experience something like this, I recommend the book.


Prof. Dr. Michael Kempe, Head of Leibniz Archiv and Forschungsstelle Leibniz in Hannover