As a Nobel Laureate in physiology or medicine in the autumn of 1963, Sir John Eccles missed the 1963 Lindau medicine meeting and was first invited to the medicine meeting in 1966. He accepted the invitation and lectured on the functioning of the neural machinery in the central nervous system, a topic close to the research which had been rewarded with a Nobel Prize. As with a certain subset of the Nobel Laureates, it seems that Sir John then fell in love with the Lindau Meetings, because he returned for all the medicine meetings for almost 30 years and lectured at each of them. On top of this unusual participation, he also lectured at the 1980 chemistry meeting, the present lecture. One might think that this was connected with his initial interest in the chemical signalling system in the nervous system. But in 1980, the retired Sir John, now living in nearby Switzerland with his wife Lady Helena, had changed his interest to the so-called mind-body problem, on which he would publish extensively until his death. Books by Sir John, one with the philosopher Karl Popper as co-author, have titles as ”The Self and its Brain”, ”The Human Mystery” and ”The Human Psyche”. They treat one of the most difficult problems we can think of, the problem of self-consciousness, the highest mental experience as described by Sir John in the lecture. There are several parts of the problem, one having to do with the theory of evolution. When did self-consciousness appear in the early pre-human beings that eventually became homo sapiens? Another part of the problem is connected with the brain as a computer, how does the machinery work? Also, is it sufficient to have a powerful computer? Since there has been some fundamental breakthroughs recently in our understanding of how the brain can adapt itself to new knowledge, in a sense re-build itself, it would have been wonderful to have Sir John lecture again at the next medicine meeting in 2014! Anders Bárány