ABSTRACT
The more detailed exploration of the relationships between human populations, resource use and environmental impact has been explored by Paul Ehrlich in a number of papers in relatively specialized journals, as well as in sources with a wider circulation. Although Ehrlich has had a high public profile in the USA and in certain world forums, most people are influenced by his published work. Ehrlich has consistently defended his fundamental ideas, maintaining that facts and science prove them to be correct. Ehrlich's role can perhaps be measured by the fact that this question is now always part of the schedule in any serious environmental debate or research programme. Ehrlich's contribution to environmental thought since the later 1960s has been characterized by his energetic lack of fear. To engage for half a century in continued controversy with a powerful opposition, while still producing basic science, is an example of stamina which deserves every plaudit.
