Basic English was published in 1930 by CharlesKayOgden and claimed to be English reduced to a vocabulary of 850 words, yet still suitable for uses in commerce, science, and the arts.
C. K. Ogden worked about the meaning of words and tried to reduce the necessary vocabulary to express meaning to a minimum. E.g., he managed to work with only 16 verbs (he called them operators). In ThelopLanguage, I follow similar lines of thought. -- HelmutLeitner
See also SimplifiedEnglish.