In this chapter I focus on how evolutionary theory challenged the preexisting ideas of perception and aesthetics, and how Galdós's writing charts this upheaval in aesthetic ideology, centring predominantly on the apparent clash between Platonic and Darwinian principles. Furthermore, Galdós's choice of metaphor, particularly in relation to the body, is explored, as are his attempts to understand his own creativity within evolutionary and transformational terms. However, when considering how a sense of aesthetics may have been developed, it is necessary to note that in this case (that is when dealing with the natural sciences in the late nineteenth century), the very means of perception of beauty and of Art was itself under fresh examination. I therefore start with an analysis of that area of the Darwinian debate related to humanity's most obvious means of perception, the human eye, and how this debate had both immediate and less direct influences on Galdós's fiction.

In the second half of the nineteenth century the human eye became part of the battleground between Darwin's supporters and his detractors. The eye represented a level of perfection in humanity and, unlike the brain or the soul, it could be readily dissected and its components examined. Whether this organ was the work of God or the product of natural processes, however, could not be investigated in the laboratory and was open to much speculation. With regard to this contentious area, Darwin finds himself having to bring God into the equation, or at least the ‘Creator’. In ‘Difficulties of the Theory’ in The Origin of Species, discussion of ‘Organs of Extreme Perfection and Complication’ is limited exclusively to the eye, and Darwin finds himself pleading for understanding on the development of the eye lens and compares it to humanity's invention of the telescope: