Although Square Form is seemingly abstract, many of Moore’s sources were representational. A frequently cited influence is ancient Mexican sculpture, in which he had been interested from the time of his earliest carvings. He explained, ‘I’ve always had a liking for squareness. The squareness of a right angle is a very vigorous action. This may be one reason why I appreciate Mexican and particularly Aztec sculpture.’  His earlier carvings that demonstrate influence from Aztec sculpture seem to suggest that he did not have confidence in completely transforming a square block of stone into a figure. However, in Square Form he is consciously utilising the right-angles of the block as the fundamental aspect of the composition.
Moore carved four works titled Square Form in the 1930s in different stones. He described green Hornton stone as having the ability to be polished to a higher degree than brown Hornton stone, which he used for another Square Form.  He used this quality, and polished the sculpture to emphasise the roundness of its curves. Moore selected Hornton stone, which comes from a quarry in Oxfordshire, because at the time he believed that an English sculptor should use English materials. Furthermore, he wanted to use materials that were not typical for sculpture.  He discovered particular stones by visiting London’s Geological Museum (now the Natural History Museum). Another advantage may have been that the local stone was cheaper than an imported material more traditionally used for sculpture.
Judith Collins writes that when the earlier artists Eric Gill, Henri Gaudier-Brzeska and Jacob Epstein had been creating cuboid sculpture before the war, it was because they were celebrating direct carving. However, when the squared forms with flat planes reappeared in sculpture in the 1930s, she links it to contemporaneous geometric painting.  The most direct link between Moore’s Square Form and painting is with the work of Ben Nicholson, who had been Moore’s neighbour since the early 1930s. Nicholson’s compositional interplay between squares and circles in his White Reliefs resonates with Moore’s sculpture. In fact Sophie Bowness describes an earlier Square Form (1934), alongside another work, Carving (1936), as ‘Two of Moore’s most Nicholsonian sculptures’. 
Tania Moore, September 2020
 John Hedgecoe and Henry Moore, Henry Spencer Moore (Nashville, Tennessee: Thomas Nelson, 1968), p.55.
 Interview between Henry Moore and Robert Sainsbury, 30 September 1982. Transcript Sainsbury Research Centre archive, p.13.
 Gemma Levine, Henry Moore: The Artist at Work, Photographed by Gemma Levine (London: Sidgwick & Jackson, 1984), p.146.
 Judith Collins, ‘Plastic form and truth to materials’, in Michael Harrison (et al), Carving Mountains (Cambridge: Kettle’s Yard, 1998), p.29.
 Sophie Bowness, ‘Modernist stone carving in England and “the big view of sculpture”’ in Harrison, 1998, p.40.
'Henry Moore at Dulwich Picture Gallery', Dulwich Picture Gallery, London, 12/5/2004 - 12/9/2004
'Henry Moore and the Challenge of Architecture', Henry Moore Foundation, UK, 2006
'Henry Moore', Tate, London, 24/2/2010 - 8/8/2010
Steven Hooper (ed.), Robert and Lisa Sainsbury Collection, volume 1 (Norwich: University of East Anglia, 1997)
Ann Garrould, Terry Friedman and David Mitchinson, Henry Moore Early Carvings 1920–1940 (Leeds: Leeds City Art Gallery, 1982)
Ann Garrould, Anita Feldman Bennett and Ian Dejardin, Henry Moore at Dulwich Picture Gallery (London: Scala Publishers, 2004)
Chris Stephens (ed.), Henry Moore (London: Tate, 2010)
Tania Moore, Henry Moore: Friendships and Legacies (Norwich: Sainsbury Centre, 2020)
Purchased by Robert and Lisa Sainsbury from the Leicester Galleries in 1936.
Donated to the University of East Anglia in 1973 (Sainsbury Centre).
Title/Description: Square Form
Artist/Maker: Henry Moore
Object Type: Sculpture
Materials: Hornton stone
Measurements: h. 360 x w. 370 x d. 200 mm
Accession Number: 83
Historic Period: 20th century
Copyright: © Reproduced by permission of the Henry Moore Foundation
Credit Line: Donated by Robert and Lisa Sainsbury, 1973