Ernst Friedrich "Fritz" Schumacher was an internationally influential economic thinker, statistician and economist in Britain, serving as Chief Economic Advisor to the UK National Coal Board for two decades. His ideas became popularized in much of the English-speaking world during the 1970s. He is best known for his critique of Western economies and his proposals for human-scale, decentralized and appropriate technologies. According to The Times Literary Supplement, his 1973 book Small Is Beautiful: a study of economics as if people mattered is among the 100 most influential books published since World War II. and was soon translated into many languages, bringing him international fame. Schumacher's basic development theories have been summed up in the catch-phrases Intermediate Size and Intermediate Technology. In 1977 he published A Guide For The Perplexed as a critique of materialist scientism and as an exploration of the nature and organization of knowledge. Together with long-time friends and associates like Professor Mansur Hoda, Schumacher founded the Intermediate Technology Development Group in 1966.