At what stage did Walters isolate the 'koru' motif for special attention? That is rather hard to pinpoint. Certainly in 1956 he made several small works on paper in which the 'koru' is set out horizontally and simplified. But the ends curve organically as in Māori art, and the motif is not fully absorbed into a frame-work of geometric elements. Triangles and circles mingle somewhat uneasily with the hand-drawn 'koru' bulbs as they struggle to accept the imposed order. As yet the 'koru' motif is one of a number of Polynesian and Micronesian designs Walters incorporated into his art at that time, and not the dominant one. In fact, a stylised totemic figure to be seen in some recent paintings, appears to have attracted more of the artist's attention. From a gradual process of trial and error, and out of the realisation that there was no need constantly to invent new forms, he isolated a severely geometric version of the 'koru' as a personal signature theme.
Perfecting that motif took some eight years of dedicated labour. In.-its final form, as seen in works from the first New Vision show of 1966, it is incredibly simple - so right that it seems obvious and inevitable. The free-flowing, hand-drawn 'koru' becomes a straight band of tone, its 'bulb' a circle. Now the incorporation of circles, as in Painting No.8 1965, appears perfectly consistent and part of the same geometric alphabet. So, too, do the bands and blocks of colours. The interplay of positive and negative is stated unequivocally through the restricted range of formal elements. Unlike Māori 'koru' patterns, positive and negative are identical in shape in Walters' works so that our perception of their relationship is immediate and insistent. Also, the much greater sharpness and precision of the shapes, compared with Māori painting, move Walters' imagery away from the associations of a hand-made artefact to those of a machine-made product from the primitive to the modern cultural context.
Already in the 1966 show Walters suggested the wide range of possibilities available within the 'koru' motif. Because he spent years making studies on paper before committing himself to canvas it, often happens that the date of a painting tells us little about the time it was first conceived. For example, Painting No.8 1965 - unusual in the retention of red ochre, black and white, colours closely associated with Māori art - shows on the right-hand side the vertical stacking of , elements he returned to later in the Genealogy series. This picture is relatively stable, and free from the dazzle and after-images associated with the well-known Painting No.1 1965, in the Auckland City Art Gallery, where the bars of black and white are narrower and more numerous. There the rapid movement of the eye from black to white reading seems to be quite unlike the slower pace required by Painting No.8 which was in the same show. Normal stylistic criteria do not seem to apply very well when each painting is engineered to be distinct from another.
Walters described his aims at the time as follows: My work is an investigation of positive/negative relationships within a deliberately limited range of forms; the forms I use have no descriptive value in themselves and are used solely to demonstrate relations. I believe that dynamic relations are most clearly expressed by the repetition of a few simple elements.
While there is no mention of a specific interest in the effects achieved by contemporary European 'Op' artists; it is tempting to draw some parallels. like, many 'Op' artists, such as Bridget Riley, Walters prefers black and white to colour. Black and white has the advantage of giving maximum contrast; it is dynamic, and most optical effects are readily achieved with it. The hard-edge quality of Walters' painting, too, gives the crisp definition of form basic to much 'Op' art. In the insistent beat of the 'koru' motif, as in Genealogy 1974, there is the repetition of geometric shapes so essential in the periodic structures of 'Op'. Certainly, many of Walters' paintings have side-effects identical with those of European 'Op' art. These include dazzle, after images, traces of colour, and suggestion of movement or shimmer. In coloured works, such as Blue and Yellow, 1967, because we are forced to view the colours simultaneously, we get traces of their complementaries and a range of perceptual effects seemingly happening in front of the picture plane.
During the twelve years since the first New Vision exhibition, Walters has shown the wide range of compositions possible within his 'deliberately limited range of forms'. Instead of being limited, he has been forced to find new solutions for each picture. At times he has worked with severe economy, deploying only a few motifs on the perimeter of a square or rectangle; he has massed whole armies of motifs one above another in his Genealogy series; or he has allowed flowing, almost lyrical dispositions, as in Blue and Yellow, where they move up and down the canvas as if in rhythm with some unheard music. Harsh juxtapositions of black and white contrast with a muted delicacy of tone and colour in a work like Rapa 1971. Without seeing a representative group of these remarkable works together it is hard to visualize how they comment on one another. But one thing seems certain: collectively they form one of the most important groups of paintings made in this country since the war.
- from Michael Dunn, 'The Enigma of Gordon Walters' Art' http://www.art-newzealand.com/Issues1to40/walters.htm