Asher Lev is a Jew child in Brooklyn, and perhaps, in the intentions of his creator, Chaim Potok, a loose portrait of painter Marc Chagall. The world, as seen through Asher Lev's eyes, becomes a pictorial representation: in his hands, things and people shift to plastic shapes and diversity of colors. But his orthodox Jew background, hostile to depictions and images, will greatly hinder Asher's calling, especially when he will try to paint crucifixions. All the same, Asher Lev explores the synesthetic value of color, to apply it to his painting. "I sat at the table, looking at the milk in the glass. Ice is white, I thought. White like milk. No, not like milk. There's blue within. And gray. […] 'What color is the feel of cold?' I asked. Mrs. Rackover stopped drying the cup she held, and stared at me. 'What?' she asked. 'The feel of cold,' I heard myself say, 'it's the feel of darkness.' […] Ice is blue, gray and white, I thought. Then I thought, no, it isn't blue, gray, and white. I don't know what color it is. It bothers me not knowing. I felt troubled and annoyed. What color is ice? I squirmed on my chair. […] In my room, I lay on the bed, closed my eyes, and thought of the man from Russia. I could see his face clearly, his roving eyes, his beak of a nose, his faded features. That face had lived eleven years in a land of ice and darkness. I couldn't imagine what it was like, to live in ice and darkness. I covered my eyes with my hands. There was his face, perfectly defined; not exactly his face, but rather the way I felt about his face. I drew his face within my head. I went to my desk, and on a new piece of paper, I drew how I felt about his face. I drew the kaskett. I used no colors. The faced stared at me from the paper. I went back to the bed, laying with closed eyes. Now within me there were ice and darkness. I could feel the cold darkness seep into me. I could feel our darkness. It seemed to me that we were brothers, he and I, that we both knew lands of ice and darkness. His was in the past; mine in the present. His was outside him; mine was within me. Yes, we were brothers, he and I, and in that moment I felt closer to him than anyone else in the world." (pp. 35 ff.)

Asher Lev needs to close his eyes to picture to himself what he cannot imagine, and to tap into reality's inner and most secret core. But Asher Lev is also a master in the practice of synesthesia. The phenomenon has long ceased being regarded as a condition, pathology or the exclusive sphere of artists and poets. In truth, literature and music offer well known and stunning instances of synesthesia: Rimbaud, in his poem Vowels, matches to each vowel a color, not just because of sound, but also following the evocative reminiscences belonging to both the color and the vowel itself. Baudelaire, in his poem Correspondences, states the intrinsic affinity linking colors, scents and sounds. Russian composer Skrjiabin, in his Prometheus, links sounds with colors, based on scientific premises like the physical structure of the light spectrum. Skrjiabin matches C with red, G with red or orange, E with blue or purple.

Previously, in 1739, the Jesuit Father Catel had tried to make music accessible to deaf persons by devising an ocular harpsichord, that combined colors using lamps and tinted glass to suggest musical combinations.

Synesthesia is far more widespread than most people think: for instance, where would a Dario Argento movie be, without its terrifying soundtrack? A rose's scent enhances its color, and even a top model with a squeaky voice would lose some of her appeal.

Of course, each sense is self-sufficient in its own operational field: you cannot, for instance, literally see sounds with your eyes. Still, as Marco Mazzeo states in his well-researched essay on synesthesia, "stimulation of a sense shall automatically trigger a perception in another mode, without any direct stimulus." (p.266). Our perception is not monosensorial: access to the world, as Max Scheler claimed, is many-sided: "On the one hand, our senses differ from each other because each questions the world around us in its own way, giving us access to facets of experience that overlap without quite coinciding." (Scheler, p.303). Indeed, the normally sighted cannot assume to experience the blind's world by just closing their eyes. Nonetheless, recognition of synesthetic perception, beside challenging the age-old pre-eminence of sight in Western culture, could attach to vision itself a greater depth and awareness, offering a "new outlook" on the meaning of "seeing".