Digital notes aren’t physical, but they are visual. They turn vague concepts into tangible entities that can be observed, rearranged, edited, and combined together. They may exist only in virtual form, but we can still see them with our eyes and move them around with our fingers. As researchers Deborah Chambers and Daniel Reisberg found in their research on the limits of mental visualization, “The skills we have developed for dealing with the external world go beyond those we have for dealing with the internal world.”2
