In Sol III, 1966, the inner square is framed by fine white lines of varying width, giving the illusion of roundness and of a light that emerges from behind. This is a fleeting glimpse of an effect that will be fundamental in different ways for the Temple and Translumina series. The Sol series extended to five, executed over three years.

The breathtaking pace of '65 was surpassed the very next year in which he completed, according to the careful accounting in this catalogue raisonne, forty-four works in different mediums. Despite the pleasant distraction of a major retrospective organized in his honor at the Cleveland Museum of Art, Anuszkiewicz in 1966 experimented with modules of black and white paintings and constructions, sometimes incorporating mirrors, based on radiating vectors. These are the only works of his career that do not employ lines to influence color shifts. "I did a painting with a grid pattern of white lines on a black background. It had two expanding corners and two contracting corners. In other words it was a square. But it appeared a distorted square, so that there was this tremendous spatial illusion on this very flat surface."⁶³ He had tried the same idea in color, but found that the kinds of illusion that he was seeking were more effective in black and white.

"The idea intrigued me so much that I spent a lot of time thinking about it... and I got this idea of doing a whole series just based on this one painting [Grand Convex, 1966], either multiplying it or changing the groupings, or cutting it into sections and regrouping it... My approach to painting is a kind of problem-solving one. I've always set out to experiment with some idea — some visual idea — to solve for myseif."⁶⁴

Anuszkiewicz's innovations were displayed in full at his second Janis show in October of 1967, which amounted to a tour de force. The gallery walls were dominated by the emblematic red squares in every possible permutation, while a section was reserved for black and white paintings as well as two constructions in which he experimented in "shape illusion" on two- and three-dimensional surfaces."⁶⁵ Infiexion, 1967, was featured in H.H. Arnason's authoritative History of Modern Art: "He skillfully reverses the direction of the radiating lines on each side of the square, thus making what at a quick glance looks like a traditional perspective box, suddenly begin to turn itself inside out."⁶⁶ Later that year, as artist in residence for a semester at Dartmouth College, he good-naturedly wrapped a pigskin football in one of his grids and donated it to the school. Using the fine arts to improve the applied was a tenet of the Bauhaus philosophy he had absorbed from Albers.

The "hidden structure" of the square fascinated Rudolf Arnheim, who begins Art and Visual Perception with a chapter on its investigation. Anuszkiewicz's involvement with regular networks of black and white squares inevitably led him to translate his research into color. For his next show at Janis, 1969, he presumably surprised his dealer by sending paintings that were yet another creative development. John Canaday's review for The New York Times speaks for itself:

Saturday, April 5,1969
Richard Anuszkiewicz: It's Baffling, by John Canaday

Richard Anuszkiewicz's exhibition of recent work at the Sidney Janis Gallery, 15 East 57th Street, is dazzling, a word that has to be got out of the way immediately because it is almost too obvious to use yet too accurate to avoid.

These paintings are also, as nearly as I can figure out, works of art created entirely by calculation. Since they are also executed with mechanical precision, they seem to contradict a premise I have always held and am unwilling to relinquish, which is that no painting of real interest can be produced entirely by rule.