Presentation Speech by Professor Sven Lidin, Member of the Royal Swedish Academy of Sciences; Member of the Nobel Committee for Chemistry, 10 December 2011
Your Majesties, Your Royal Highnesses, Ladies and Gentlemen,
For three millennia we have known that five-fold symmetry is incompatible with periodicity, and for almost three centuries we believed that periodicity was a prerequisite for crystallinity. The electron diffraction pattern obtained by Dan Shechtman on April 8, 1982 shows that at least one of these statements is flawed, and it has led to a revision our view of the concepts of symmetry and crystallinity alike. The objects he discovered are aperiodic, ordered structures that allow exotic symmetries and that today are known as quasicrystals. Having the courage to believe in his observations and in himself, Dan Shechtman has changed our view of what order is and has reminded us of the importance of balance between preservation and renewal, even for the most well established paradigms. Science is a theoretical construction on an empirical fundament. Observations make or break theories.
“We are like dwarves on the shoulders of giants, so that we can see more clearly than they, and things at a greater distance, not by the virtue of any sharpness of sight on our part, but because we are carried high and raised up by their great size.” This metaphor, first used by Bernard of Chartres and later by Newton and many others, hails back to antiquity and to the blind giant Orion who carried the servant Cedalion on his shoulders in his quest for the uttermost east where the sun would heal him of his blindness. The myth illustrates the progress of science. Each generation takes knowledge a little further because it builds on the results of its forebears. The image of the amassed knowledge as a blind giant with a seeing dwarf on its shoulders is an idealisation of science at its best: A relationship of mutual trust between the bearer and the borne, between the blind and the seeing. The giant provides established truths. The dwarf strives for new insight. Like every good metaphor this one not only describes the benefits of the arrangement, it also hints at the dangers.
The relation between the dwarf and the giant is fundamentally asymmetric. The dwarf can see, but the giant decides on which road the two shall take. The dilemma of the giant is that he is at the mercy of the dwarf, but he cannot trust him blindly. The paradigms of science are challenged daily on more or less solid grounds and the difficulty is to know when to take these challenges seriously. The dwarf faces the reverse problem. He depends on the giant, and without him he gets nowhere despite the clarity of his vision. In order to make his own choices he is forced down on the ground, to walk alone without the support he enjoyed on the shoulders of the giant. This year’s Chemistry Laureate was forced to do battle with the established truth. The dwarf doesn’t serve the giant by subservience but through independence.
Coming down from the shoulders of the giant is a challenge. Not least because those that remain aloft are tempted to look down at those on the ground. The disbelief that met Dan Shechtman was appropriate and healthy. Questioning should be mutual to promote the growth of knowledge. The ridicule he suffered was, however, deeply unfair. It is far too easy for all of us to remain in our lofty positions, and with lofty disdain regard the fool who claims that we are all wrong. To be that fool on the ground takes great courage, and both he and those that spoke out on his behalf deserve great respect.
Your discovery of quasicrystals has created a new cross-disciplinary branch of science, drawing from, and enriching, chemistry, physics and mathematics. This is in itself of the greatest importance. It has also given us a reminder of how little we really know and perhaps even taught us some humility. That is a truly great achievement. On behalf of the Royal Swedish Academy of Sciences I wish to convey our warmest congratulations, and I now ask you to step forward and receive your Prize from the hands of His Majesty the King.