This question implies a "heroic" philosophy of science to which I do not subscribe.

I think that in general break-through thoughts are the product of individuals and not institution that mainly popularize and spread the thoughts, break troughs - or flash-points as I called them in my ASAIO presidential address. I also think that these "historical moments" are the result of numerous building blocks created by generations. Flash points then often occur simultaneously by several individuals often working without contact with each other. They cannot take place without the previous - undramatic but often more ingenious then the "break-through. Think about the importance of Thomas Graham's separation of small and big molecules - that was the most important single discovery and experiment for the development of dialysis. But it was much, much less dramatic than the first dialyses of patients.

Fame is different, as it is mainly the result of intense efforts of beatings ones own drum. "Funny thing with fame, you have to work on it all the time" I think that quote is from "Paper moon". So the "historical moment" may more often be the result of actively seeking fame than the worth of an idea or device. To illustrate what I mean, think about the most influential idea of our century - the relativity theory by Einstein. Einstein formulated this working as a clerk in a patent bureau in Switzerland - if I have my history right. Fame - but no more breakthroughs occurred when he was idolized - and institutionally shackled in the USA.

In dialysis I think perhaps the "heroic" moment occurred in the early 1940's. A flash point then occurred when simultaneously Alwall in Sweden, Kolff in Netherlands and Murray in Canada independent of each other, developed clinically useful artificial kidneys. But; they all built on over two centuries of published discoveries and experiments with membranes, molecular separation, and understanding of uremia and development of anticoagulation. Without that background of knowledge, engineering and clinical experiments of each component an artificial kidney was not possible. The resulting dramatic emergence of dialysis is then, in my view more like a gigantic building were brick-layers, carpenters, plumbers, the discovery of firing clay and so on, are a more likely explanation then God touching the finger of an Adam. The fate of the three devices was different: Alwall's device was by far the most ingenious and elegant. As a result it had widespread use for over 20 years. Most of the early clinical experience with dialysis was with that device. Dialysis quantitation, the importance of fluid overload, the dialysis for intoxications - all came out of work with the device. It was the only one of the three early artificial kidneys that could do ultrafiltration easily and efficiently and as consequence Alwall early realised that fluid overload was a more important part in "uremic" death than uremia itself. Kolff took his device to the USA, that gave him the best platform, and put him in contact with Harward and John Merrill and later Baxter who further helped him develop his ideas. The rotating drum was a mechanical nightmare and clumsy to use. But Kolff's early pioneering thoughts of uremia and how to treat it and his two early monograph books about it were landmarks. Gordon Murray seems to have been one of those people who sprout ideas and then leave them behind for others to play with. His device was not efficient enough but an elegant engineering solution. I do not have any knowledge that it spread beyond Toronto. He seemed to have been difficult to deal with for institutions. He was a true pioneer also in the use of heparin and bubble oxygenators. He had a somewhat ignoble fate when later censured for unsupported claim to have made severed spinal cords come together.

This is perhaps a longer answer than wished for but this is how I see the history of science.

[NOTE: See John Watson's reply to this observation.]