Cataracts forced him to change his style.’Water Lilies’ exhibit could use less padding, more paintings.

The High Museum’s “Monet’s Water Lilies” confirms that the Impressionist painter ended his artistic career just the way he started it: as a radical.

Monet the Young Turk shocked the public in the late 1860s with landscape paintings that looked, to the 19th-century taste, decidedly unfinished. Prodded by scientific discoveries about the nature of color and perception, he was attempting to convey the sensory image the way it arrives in our brains, as opposed to the way our brains and our art conventions repackage it.

This was a conceit, but a productive one. It also led to his innovative serial paintings, in which he depicted a single subject —- haystacks, Rouen Cathedral —- at different times of day and year. This tactic made light, atmosphere and color the de facto subject —- a concept he emphasized by presenting them as a group, lined up around gallery walls.

By 1918, the time of the High’s exhibit, the 78-year-old artist, who had claimed he wanted to be just an “eye,” was struggling with the fact that his eyes were failing him. Cataracts had blurred vision and impaired color perception. As these four paintings demonstrate, he surmounted his limitations, and then some. In the last 10 years of his life, he moved to the brink of abstraction.

The first two paintings in the show are transitional, perhaps unfinished. Monet uses looser, broader, multi-directional brush strokes, but the objects in the landscape are still clearly delineated. Comparing them to “Water Lilies,” hanging on the adjacent wall, there’s no mistaking that he’s turned a corner. Expanded to monumental scale, the lily pond has dissolved into touches of color —- blues, pinks, mauves, greens —- with only the barest allusions to blooms and pads.

The climactic painting —- a triptych 42 feet long —- represents the water-lily series in full bloom, as it were. “Reflections of Clouds on the Water-Lily Pond” is the perfect balance of freedom and control. Despite creating what he called “the illusion of an endless whole, of water without horizon or bank,” Monet has subtly orchestrated color and form into a rhythmic composition. He has layered and scraped colors to convey a watery depth, while dancing his brush along the surface. The brushwork is dynamic but the effect, unlike the transitional pieces, is serene.

This piece was among the candidates for the water lily installation at the Orangerie in Paris. His vision, a natural extension of his earlier presentation of the serial paintings, was to encircle the oval room with these majestic paintings to create an immersive, meditative environment. The only comparison that comes to mind is the Rothko Chapel in Houston, which engulfs the visitor in the Abstract Expressionist’s glowing paintings. It’s a telling one: In the water lily paintings, Monet moves from the physical to the metaphysical.

These four paintings from the Museum of Modern Art and the accompanying text the High developed make for a substantive look at Monet’s last burst of creative energy. But the High lessens the impact by stretching the show through too many galleries and filling the empty spaces with photographic blow-ups. Something’s amiss when wall texts take up more space than actual objects.

Instead, the High could have made use of the Monets in its own collection. “Autumn on the Seine at Argenteuil” (1873) and “Houses of Parliament” (1903) suggest his evolution. They show the dissolution of the object and the expanded scale.

They document his ongoing fascination with water, reflections and atmosphere. They would have brought home dramatically the magnitude of conceptual and visual leap the water lily paintings represent.