ABSTRACT
Through what capacities, and for which purposes, were images considered to be particularly useful knowledge tools in comparison to the medium of text? This chapter investigates what ideas medical-astrological books reflect – explicitly and implicitly – on how images help to convey knowledge. My analysis focuses on images with mainly analytical features as they are, by their nature, intended to convey certain types of knowledge. 1 As ‘a visual “this is”,’ they imply, or indeed claim, to demonstrate what something looks like, or how it works. 2 Therefore, they are epistemic images according to the definition of historian of science Christoph Lüthy: they have a ‘general function of helping to “understand” a given theory or truth, irrespective of its “scientific” status.’ 3 That they have this function of fostering comprehension is also reflected in the texts: analytical images are frequently referred to in the texts, in ways that narrative images are not. As we will see, the verbal rhetoric of these explicit textual references is highly revealing of the perceived epistemic significance of images.
