Chemophobia literally means "fear of chemicals". It is most often used to describe the assumption that "chemicals" (i.e., man-made products or artificially concentrated but naturally occurring chemicals) are bad and harmful, while "natural" things (i.e., compounds that occur naturally or that are obtained using traditional techniques) are good and healthy. General chemophobia derives from incomplete knowledge of science, or a misunderstanding of science, and is a form of technophobia and fear of the unknown.