These two disciplines focus on the same graphical–visual phenomena-text-but from different viewpoints. Our goal is to review key ideas on the distribution and effects of print size from the two very different disciplinary perspectives of vision science and typography. While economic, social, technological, and artistic factors influence type design and selection, we conclude that properties of human visual processing play a dominant role in constraining the distribution of print sizes in common use. We discuss theoretical concepts from vision science concerning visual size coding that help inform our understanding of historical and modern typographical practices. We provide new data on the distributions of print sizes in published books and newspapers and in typefounders' specimens, and consider factors influencing these distributions. Assuming a standard reading distance of 40 cm (16 inches), the corresponding physical x-heights are 1.4 mm (4 points) and 14 mm (40 points). The fluent range extends over a factor of 10 in angular print size (x-height) from approximately 0.2° to 2°. We present evidence supporting the hypothesis that the distribution of print sizes in historical and contemporary publications falls within the psychophysically defined range of fluent print size-the range over which text can be read at maximum speed.

In this paper, we focus on print size because of its crucial role in understanding reading performance and its significance in the history and contemporary practice of typography. The size and shape of printed symbols determine the legibility of text.

Font size to actual size in inches