It has been distinguished when it was first proposed due to the way it introduced a degree of arbitrariness. It is also based on a classificatory system and uses 37 basic signs and 21 standard hand postures, which can be combined to represent a large vocabulary of English words, including word endings and verb tenses.
PGSS was originally developed in Britain by anthropologist Sir Richard Paget in the 1930s,  and later by his wife Lady Grace Paget and Dr Pierre Gorman. The system is founded on the notion that the original form of all speech is sign language and it has developed to the point that it features its own grammatical sign system.