How does the stream-of-consciousness form of “The Mark on the Wall” support its content?

At the time she wrote "The Mark on the Wall," Woolf was quite enthusiastic about the work of James Joyce (if somewhat uncertain about the early chapters she saw of Ulysses), praising him for his ability "to reveal the flickerings of that innermost flame which flashes its messages through the brain." In summarizing her own technique in "The Mark on the Wall," she described those messages as "myriad impressions" which she listed as "trivial, fantastic, evanescent, or engraved with the sharpness of steel." Her efforts to record the flow or stream of consciousness paralleling what Joyce was doing drew on two crucial, revolutionary components of Modernism. One was the work of the Post-Impressionist painters.

Roger Fry immediately recognized her inspiration in the work of the artists who were featured in his famous exhibition, complimenting Woolf on the "plasticity" of "The Mark on the Wall," and Woolf responded by saying "I'm not sure that a perverted plastic sense doesn't somehow work itself out in words for me." The concept of plasticity is somewhat vague, but in "The Mark on the Wall," Woolf muses over the mutability of boundaries between species or categories: As for saying which are trees, and which are men and women, or whether there are such things, that one won't be in a condition to do for fifty years or so.

As in a Post-Impressionist painting, "There will be nothing but spaces of light and dark, intersected by thick stalks, and rather higher up perhaps, rose-shaped blots of an indistinct color." The sense of abstraction, of shifting shapes and variable hues and tones undermining the absolutes of Edwardian culture, runs throughout the story. In the middle of "The Mark on the Wall" Woolf indicates an awareness of the mind's operation as it occurs—"I want to sink deeper and deeper, away from the surface, with its hard separate facts. To steady myself, let me catch hold of the first idea that passes." Here, in an anticipation of postmodernist narrative self-reflection, Woolf is illustrating the manner in which the awareness of process affects the process itself. This is a concept roughly similar to Werner Heisenberg's revolutionary Uncertainty Principle, which holds that nothing can be precisely observed since the process of observation alters the original position or shape of the object.

For Woolf, what she actually sees is much less important than the way she sees it. The actual "mark" becomes a point of departure, not the answer to her questions.