Gamow, who was a complete layman in the field of biology (some of his detractors would say almost a charlatan), proposed, with his fantastically unerring instinct, some ideas about how the code really worked. I think he was the first to suggest that the sequence of the four substances of the DNA denoted by the letters A, C, T, G, expressed words, and how from these four letters one could build twenty or twenty-three amino acids which, in turn, considered as words, combined into phrases defining the structures of proteins. Gamow had this idea before anyone else. He even almost had the correct way (later found by Crick) of expressing the formation by triplets. At first he thought four were necessary. He was almost correct from the start.
One may see in his work, among other outstanding traits, perhaps the last example of amateurism in science on a grand scale.
An overwhelming curiosity about the scheme of things in nature, in the very large and in the very small, directed his work in nuclear physics and in cosmology.
The meaning, the origin and perhaps the variability in time of the fundamental physical constants like c (the velocity of light), h (the Planck constant), G (the gravitation constant) occupied his imagination and his efforts during the last years of his life.
The great unanswered questions concern the relations between masses of elementary particles and also the very large numbers which are the ratios between the nuclear, electrical, and gravitational forces. Gamow thought that these numbers could not have arisen as a result of an initial accident, and that they might be obtainable from topological or number-theoretical considerations. He believed in the final simplicity of a theory which one day would explain these numbers.
The French fictional detective Arsène Lupin, arch rival of Sherlock Holmes, said: "Il faut commencer à raisonner par le bon bout." (You have to start thinking from the right end.) Gamow had a particularly great gift for this. He used models or similes; speaking mathematically he was guided by isomorphisms or homomorphisms. Abstruse ideas of quantum theory and the more palpable ideas between structures of classical physics were transformed or transfigured, not just by repetition, but by going to variables of higher time, to use technical mathematical terms again.
In 1954 Gamow and I happened to be in Cambridge, Massachusetts, at the same time. I was telling him about some of my speculations on the problems of evolution and the possibilities of calculating the rate of evolution of life. One day he came to see me and said: "Let's go to Massachusetts General Hospital — there is an interesting biology seminar." And we drove in his Mercedes. On the way I asked him who was talking. He said, "You are!" Apparently he had told the professors running the seminar that we would both talk about these speculations. And indeed we both did. On the way home I remarked, "Imagine, George, you and me trying to talk about biology! All these people, all these doctors in white smocks — they were ready to put us in straitjackets."
In conversations during the last few months of his life he often returned to the consideration of schemata that might possibly throw light on the mystery of the elementary particles and the constants of physics. In a dream he had, which he related to his wife, Barbara, shortly before his death, he described the tantalizing experience of being in the company of such great spirits as Newton and Einstein and of discovering, as they had discovered, the extreme simplicity of the ultimate scientific truths.
At the same time that he delighted in cutting to the heart of things, he kept track of all his mundane activities in a very detailed and systematic way. From the first time I met him to the end, when we were both professors on the same campus in Boulder, I remember his collecting and putting in order all manner of snapshots and pictures of his various activities, markers as it were of scientific progress, vacation trips, discussions with friends. He also loved to compose photo-montages combining his own drawings with photographic cut-outs. These were intended as illustrations or caricatures of scientific discoveries.
All his writings are characterized by a natural flow of ideas, a simple uninvolved presentation, and an easy, never redundant, amusing but never frivolous style. He wrote easily, quickly, hardly ever rewriting, filling innumerable pages, each with only a few lines handwritten in enormous characters.
His now classic books on the history of physics and on the new ideas in the physical sciences show him to have been without malice or harsh judgment towards fellow physicists. He was sparing with real praise, reserving it only for the great achievements, but he never criticized or even pointed out mediocrity.
His popular books on science received great acclaim. Among the outstanding qualities of these works are simplicity of approach and the avoidance of unnecessary technical details that also distinguished his work in research.
His honesty made him write exactly the way he thought, embodying the precept of Descartes: ''ordering one's thoughts to analyze the complex by dissecting it into its simpler parts."
One characteristic of Gamow, which was not perhaps directly visible but was easily deducible from his conversation and his creative activity, was his excellent memory. After dinner or at parties he loved to recite for the benefit of friends of Slavic origin long excerpts of Russian poetry; he could quote Pushkin or Lermontov by the hour. He also loved to use Russian proverbs.
Gamow had a ready wit and made many bons mots. He told me that the day he drove to Los Alamos for the first time, he noticed that "as one crosses the Rio Grande, and before one arrives at the Valle Grande [the Valle Grande is an extinct volcano of enormous dimensions in the mountains behind Los Alamos], one comes to the city of the Bomba Grande."
In 1949 my approaching fortieth birthday appeared as a threatening landmark in my life. I always considered it ominous to be slipping into middle age. One's feelings about age change with time, of course, but mathematicians have a reputation for peaking early, and many, myself included, have an admiration for youth. This Hellenic accent on youth is also something of an American obsession. From my earliest reading I admired Abel, the Norwegian genius who died at twenty-seven, and Galois, the creator of new ideas in algebra and group theory who died in a duel in Paris at the age of twenty-one. The greatest achievements of middle-aged men did not touch me as much. The tragedy, of course, is that as one gets older one tends to try to use old tricks in new situations; a sort of self-poisoning stops creativity. My friend Rota said he did not believe it was creativity that stopped but interest. That remark sparked a feeling of déjà vu. I agree in part. Maybe it is like boxing: it is not that the reactions slow down or that one is more easily fatigued; when boxers start having to think about what they are doing, they lose, because the reaction should be instinctive, quick automatic subroutines, so to speak.
Johnny used to say that after the age of twenty-six a mathematician begins to go downhill. When I met him he was just past that age. As time went on he extended the limit, but kept it always a little below his age. (For example, when near forty, he raised it to thirty-five.) This was characteristic of his rather self-effacing manner. He did not want to give the appearance of considering himself "in." He knew that self-praise sounds ridiculous to others, and he would lean over backwards to appear modest. I, on the contrary, always took pleasure in boasting, especially about some of my own trivial accomplishments like athletics or winning at games. Children boast quite naturally. In the literature of antiquity, notably in Homer, heroes brag openly about their athletic prowess. Scientists sometimes boast by implication when they criticize or minimize the achievements of others.