Making thoughts, ideas and plans explicit by writing them down or by developing an artifact, we create situations which talk back to us. For example, architects use the backtalk of their work extensively. When sketching, unexpecting patterns emerge, which are incorporated and maybe elaborated on in the drawing. Thus, the act of sketching is not only the conscious act of sketching the intended subject, but an interplay between the sketcher, the materials and possibly other situational constraints. Herbert Simon's description of the work proces of an oil painter illustrates the point:
"in oil painting every new spot of pigment laid on the canvas creates some kind of pattern that provides a continuing source of new ideas to the painter. The painting process is a process of cyclical interaction between the painter and canvas in which current goals lead to new applications of paint, while the gradually changing pattern suggests new goals." (Simon, 1996)
Situational backtalk is an important part of creative processes and in Schön's words, design is a "reflective conversation with the materials of the situation" (Schön, 1983). This suggests that externalized representations such as computer programs, oil paintings, and other artifacts are not simple projections of the designer's intention. Instead they are products of the designer's intentions, the materials and situational constraints.
Please note that backtalk of a situation is also known as "situational feedback".