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<\/span><\/div>\nSchr\u00f6dinger’s book inspired early DNA research, but the physicist never returned to biology.<\/p>\n
<\/p>\n <\/p>\n A refugee from the Third Reich, Viennese-born Schr\u00f6dinger had found shelter at Dublin’s Institute for Advanced Studies (1<\/em><\/a>). Required by statute to deliver public lectures every year, he chose in 1943 for his topic the physical aspects of the living cell. He lectured on three consecutive Fridays, to a packed house. The enthusiastic response spurred the publication of his notes in November 1944.<\/p>\n The book did well. In the first year, it sold 5000 copies and attracted 65 reviews. The celebrated J. B. S. Haldane mused that at a time when most physicists were engaged in war work and had a hard time keeping up with their own subject, Schr\u00f6dinger\u2014in neutral Ireland\u2014had found leisure enough to turn to another branch of science: genetics (2<\/em><\/a>). Schr\u00f6dinger had hailed the discipline as \u201ceasily the most interesting of our days.\u201d Geneticist Haldane politely wondered whether posterity would confirm that judgment. It did, not least thanks to Schr\u00f6dinger’s book.<\/p>\n What Is Life?<\/em>\u00a0became one of the most important science books ever, not for its content (whose limitations were soon evident) but for its influence on a cohort of brilliant scientists. Almost all of the protagonists of the double helix saga acknowledged, at one time or another, the impact of Schr\u00f6dinger’s book (the one possible exception being crystallographer Rosalind Franklin, who died before writing her memoirs) (3<\/em><\/a>). Many of them\u2014including Francis Crick, Maurice Wilkins, and Seymour Benzer\u2014were physicists, but some were chemists (such as Erwin Chargaff and Gunter Stent) or physicians (such as Fran\u00e7ois Jacob). Even a teenage bird watcher named James Watson became \u201cpolarized towards finding out the secret of the gene\u201d after reading Schr\u00f6dinger’s booklet (4<\/em><\/a>).<\/p>\n Schr\u00f6dinger’s prescient vision of genetic coding is one message in\u00a0What Is Life?.<\/em>\u00a0Another is that cells create order from disorder and transmit order from order. From this, Schr\u00f6dinger concluded that new physical laws were needed to explain life: \u201c,,,present-day physics and chemistry could not possibly account for what happens in space and time within a living organism.\u201d He purported to prove this by drawing on the results of mutagenesis experiments conducted by his erstwhile postdoc Max Delbr\u00fcck, which offered an estimate for gene size and implied, so Schr\u00f6dinger thought, that heredity relies on a mechanism \u201cthat cannot be reduced to the ordinary laws of physics.\u201d<\/p>\n Schr\u00f6dinger was in good company: His colleagues Niels Bohr and Pascual Jordan were also of the opinion that new laws of physics were needed to explain life. With the discovery of the double helix, however, it turned out that there was no need for new laws. The chemical gadget could be entirely explained, ironically, by the quantum mechanics that Bohr, Schr\u00f6dinger, Jordan, and others had developed in the 1920s. Indeed, the copying mechanism of genes is based on hydrogen bonds between complementary nucleotides\u2014territory ruled by the Schr\u00f6dinger equation.<\/p>\n Six months after the discovery of the double helix, and a mere 10 years after the Dublin lectures, Francis Crick sent a letter to Schr\u00f6dinger, acknowledging the impact of\u00a0What Is Life?<\/em>\u00a0on both himself and Watson. Schr\u00f6dinger did not reply. Even stranger, he never returned to biology.<\/p>\n Schr\u00f6dinger lived until 1961, when the search for the genetic code was at its height, but seems to have lost interest in \u201cthe most interesting science of our day.\u201d He had assiduously studied genetics for 20 years, but after the publication of\u00a0What Is Life?<\/em>\u00a0he turned to other things. In new editions of his seminal book\u2014which never went out of print\u2014Schr\u00f6dinger did not address the breathtaking progress that it had caused, nor Oswald Avery’s discovery that genes are made of DNA, nor John von Neumann’s bold ideas on self-replicating automata.<\/p>\n With the advent of molecular biology, the centuries-old debate between \u201cvitalists\u201d and \u201cmechanists\u201d turned decisively against the former. Schr\u00f6dinger, however, punctured the latter, in a jaunty afterword tackling consciousness. Haldane quipped in his book review, \u201cA mechanist must either give a mechanist account of life, or turn a somersault. In his epilogue, Schr\u00f6dinger does the latter with very great elegance.\u201d Schr\u00f6dinger had preempted that objection by quoting the philosopher Unamuno: \u201cIf a man never contradicts himself, the reason must be that he virtually never says anything at all.\u201d<\/p>\n <\/p>\n <\/p>\nPHOTO: BETTMANN\/CONTRIBUTOR\/GETTY IMAGES<\/q><\/div>\n<\/div>\n