Sir Alexander Fleming

Banquet speech

Sir Alexander Fleming’s speech at the Nobel Banquet in Stockholm, December 10, 1945

For many years I have read of people getting the Nobel Prize. Then I always regarded them as a superior class to which it was almost impossible to aspire. Now suddenly I find myself in that class and I wonder whether they are so different.

Did they obtain this great distinction – for indeed it is the greatest distinction a scientist can obtain – by deep thought or did Dame Fortune play a part.

We all know that chance, fortune, fate or destiny – call it what you will has played a considerable part in many of the great discoveries in science. We do not know how many, for all scientists who have hit on something new have not disclosed exactly how it happened. We do know, though, that in many cases it was a chance observation which took them into a track which eventually led to a real advance in knowledge or practice. This is especially true of the biological sciences for there we are dealing with living mechanisms about which there are enormous gaps in our knowledge.

I am here because of penicillin and perhaps the story of penicillin illustrates what I am saying.

I myself have since the introduction of Salvarsan 35 years ago been interested in chemotherapy and antiseptics. But I was really an immunologist, working in a laboratory almost entirely devoted to immunology. In 1922 by a combination of fortuitous circumstances I discovered lysozyme – one of the most interesting antibiotic substances. The extraordinary bacteriolytic power of lysozyme – a ferment present in our normal cells and secretions – especially in such supposedly inert secretion as the tears – showed me how powerful an antibiotic substance could be. Unfortunately lysozyme acted most strongly on the wrong microbes (from the medical point of view) – those which did not infect man – but it had its uses for it paved the way for penicillin for me and I think also for my partners in this Nobel Award, Sir Howard Florey and Dr. Chain.

Then in 1928 an accidental contamination of a culture plate by a mould set me off on another track. I was working on a subject having no relation to moulds or antiseptics and if I had been a member of a team engaged on this subject it is likely that I would have had to neglect the accidental happening and work for the team with the result that penicillin would not then have been described and I would not be here today as a Nobel Laureate. But, fortunately for myself – and may be for the world – I was situated so that I could leave my previous line of research work and follow the track which fate hade indicated for me.

I isolated the contaminating mould. It made an antibacterial substance which I christened penicillin. I studied it as far as I could as a bacteriologist. I had a clue that here was something good but I could not possibly know how good it was and I had not the team, especially the chemical team, necessary to concentrate and stabilise the penicillin.

It was ten years later that Florey and Chain made up a complete team at Oxford which succeeded in this and showed the marvellous chemotherapeutic properties of penicillin.

Then fortune again intervened for they obtained their results in the midst of a great war when ordinary economics are in abeyance and large scale production could go ahead as it would never have done in times of peace. The result is that in an incredibly short time manufacturing difficulties have been overcome and penicillin is being produced on a large scale.

I have been trying to use penicillin to illustrate two points.

The first is that team work may inhibit the primary initiation of something quite new but once a clue has been obtained team work may be absolutely necessary to bring the discovery to full advantage.

The second is that destiny may play a large part in discovery. It was destiny which contaminated my culture plate in 1928 – it was destiny which led Chain and Florey in 1938 to investigate penicillin instead of the many other antibiotics which had then been described and it was destiny that timed their work to come to fruition in war-time when penicillin was most needed.

It may be that while we think we are masters of the situation we are merely pawns being moved about on the board of life by some superior power.

Thank you.

Prior to the speech, Professor A.H.T. Theorell, Director of the Department of Biochemistry at the Nobel Institute of Medicine, addressed the laureate: “To you, Ernst Chain, Howard Florey and Alexander Fleming, I will relate one of Grimm’s fairy-tales, that I heard as a child. A poor student heard under an oak a wailing voice that begged to be set free. He began to dig at the root, and found there a corked bottle with a little frog in it. It was this frog that wanted so badly to be set at liberty. The student pulled the cork, and out came a mighty spirit, who by way of thanks for the help gave him a wonderful plaster. With the one side one could heal all sores; with the other one could turn iron into silver. The student thereafter performed both operations, and became the most famous physician in the whole world – perhaps also the richest.

You have dug up a wonderful plaster, too, that has healed countless sores. This achievement called for years of labour, unerring instinct, profound and wide knowledge, team-work and some luck. Your penicillin was made available to mankind during the biggest of wars; but it is unable to serve anything but peaceful purposes. It cannot kill a mouse, though it can heal a man.

You have become the most famous doctors in the whole world; but there is a difference between you and the student – you have not used that side of the plaster which made silver. We follow Alfred Nobel’s intentions in giving you gold, instead of silver.”

From Les Prix Nobel en 1945, Editor Arne Holmberg, [Nobel Foundation], Stockholm, 1946

Copyright © The Nobel Foundation 1945

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