SummaryThomas Addis came of evangelical Scots stock; he was brought up to care for others less fortunate than himself, to know what he believed in and to defend it vigorously. Trained at the turn of the 19th and 20th centuries in a Scotland still recovering from wars and ecclesiastical schisms, yet producing record numbers of missionaries and many social improvements, he was a brilliant haematologist and innovative researcher. Moving to Stanford his career continued to blossom as a nephrologist whilst his concern for the less fortunate found expression in his espousal of communist principles. Only in his later years was he finally honoured for his many contributions to medicine, science and social issues.