Pick up a work by Shah Waliyullah of Delhi (d. 1762), the great Indian polymath and sage-like figure, and he might commend your attention to sensory substitution, or synesthesia – what we can think of as cross talk among sensory areas in the brain. Indeed, Waliyullah is but a premiere example among many Medieval and early modern Muslim theologians who offer startling insights about perception, ideas which sometimes even resemble trending topics like neuroplasticity. I say this mindful of the warning not to mold our “notion of antiquities after their resemblance to the present”(Funkenstein, 120).
A bridge between theology and culture
Waliyullah wrote masterfully on Islamic law, spirituality, the Qur’an, and the Prophetic traditions. In these works, he tried to explain how revelations and intuitions are mediated by the human mind, particularly the minds of prophets. In my reading it appears that he tried to build a bridge between theology and culture. His point was to show that while the minds of prophets are in one sense attuned to the celestial spheres, other aspects of their minds refract the maps of their respective cultures. Of particular importance to him were the specifics of law, norms and values that were encoded in revealed religions like Islam at its very inception in the seventh century. For most Muslim thinkers and theologians the relevance of norms and values were never in dispute. Yet, often the form and practice of such norms and values sparked debate. Wrestling with these problems forces figures like Waliyullah to grasp the nettle of the metaphysics and the sociology of revelation.
It is thrilling to know that Muslim theologians of earlier generations relied on varieties of knowledge of their time in order to explain and make their theological claims understandable. For theologians like Waliyullah it was almost a matter of necessity to construe a theology that took the empirical aspect of the human person seriously. In his view, theological strictures were often subordinate to the contemporaneous reality of the human being, whether in terms of psychology or sociology avant la lettre, or with the aid of other disciplines of the day like philosophy and metaphysics.
To make his argument forcefully, Waliyullah proposes what might be akin to indelible cultural maps to which our minds are formatted. Instead of viewing our minds as exclusively neural, Waliyullah implies we might think of ourselves as neuro-cultural beings. And prophets too are not immune from the cultural mapping of their minds and personas. Their revelations are encoded and mediated by the same cultural maps that their communities project. Waliyullah’s most developed excursus on this topic comes in ‘The Fourth Vision” of his Emanations in the Two Holy Shrines-Fuyuz al-Haramayn.
If a congenitally blind person dreams, Waliyullah asks, how does he see things? How does a congenitally deaf person hear, in his dreams? Well, he explains, persons with such deficits see or hear with the help of what we would call sensory substitutions or the blending of the senses. Persons with sight disabilities, in his words “cannot in their dreams see colors or forms, instead they see themselves touching things, hearing voices, tasting or smelling things in their dreams.” (Fuyuz, 90). Similarly, a congenitally deaf person never hears things in his dreams but is restricted to rely on his other sensory organs for information to substitute for sight or hearing.
Sensory substitution is crucial for Waliyullah. Why? Because examples of dreamers with sensory deficits allow him to make the case that “pre-existing forms and ideas,” – what I have called cultural mapping – do exist. These pre-existing forms or cultural maps in the mind of the dreamer become the building blocks—alphabet and language—in which dreams are experienced.
Waliyullah sets up this example to make his major point: revelation vouchsafed to the prophets is organically and culturally related to the worlds the prophets inhabited. How? What prophets speak or teach is derived from their environments and cultures and is first and foremost preserved in their minds. Therefore, he says, when prophets disclose their revelations the “vocables (alfaz), words (kalimat) and syntactical forms (asalib) that were already preserved in the mind of the ‘recipient of revelation’ become manifest.” (Fuyuz, 91). This allows him to say that rules and regulations contained in revelations were always organically connected and in sync with the habits and customs of the communities to which prophets were dispatched. Is he saying that the mind is culturally wired?
I marveled at Waliyuallah’s insights—I am assuming that many theologians and philosophers prior to him held similar views—when I found David Eagleman explain neuroplasticity in his book Incognito. Consider Eric Weihenmayer who was blinded at age thirteen but who scaled Mount Everest as an adult. Today Weihenmayer climbs with a gadget containing a grid of over 600 tiny electrodes in his mouth called the BrainPort. This device, says Eagleman, “allows him to see with his tongue while he climbs.”
The blending of senses
What Waliyullah’s dreamers with sensory deficits achieve via sensory substitution is similar to Weihenmayer’s BrainPort apparatus: the dreamers see or hear with a crucial difference; they see and hear via tasting, feeling and smelling. Sensory substitution “reminds us that we see not with our eyes but rather with our brains” (Eagleman, 41). The blending of the senses is precisely one of the kinds of synesthesia involving the ‘hearing’ or ‘smelling’ of sight or the ‘touching’ of hearing. Synesthesia is believed to be seven times more common among artists, poets and novelists; in short, people who are seers of some sort. But more importantly, the mere existence of synesthesia shows that “more than one kind of brain–and one kind of mind–is possible.” (Eagleman, 80).
Contemporary neuroscience has made great strides in explaining perception. Now we know the traditional view of perception is incorrect in explaining that data from the sensorium pours into the brain and then makes itself seen, heard, smelled or tasted. Scientists now argue that the brain is a “closed system that runs its own internally generated activity.” (Eagleman, 44). Like the dreamers in Waliyullah’s illustrations who see and hear without real sight and hearing, Eagleman too confirms that during “dream sleep the brain is isolated from its normal input, so internal activation is the only source of cortical stimulation” (Eagleman, 44).
So what role do the senses play in perception? Can we completely dismiss the senses? Current knowledge of the neurocircuitry of the brain questions whether visual perception is only a procession of data crunching in a linear fashion from the eyes to the brain. Instead, what we do discover is that perception involves nested feedback connections that enable the system to run backward. Now we learn that a loopy brain enables us to “make predictions ahead of actual sensory input” (Eagleman, 48). “The more surprising aspect… ,” says Eagleman of this new framework of perception, is that “the internal data is not generated by external sensory data but merely modulated by it.” (44). So, we still depend on sensory data but we now know it surely works differently from what we thought previously.
The riddle of metaphors
Waliyullah might have wanted to emphasize the synchronic relationship between the mind and culture, but in the process he disclosed how he thought humans knew and perceived things. It is eminently possible that the blending of the senses had something to do with the pre-eminence of prophets over time, just like poets.
Furthermore, our language is replete with synesthetic metaphors (Ramachandran, 79). We talk of “loud” shirts, “sharp” cheese or “a sharp person” when none of these tactile adjectives apply to shirts, cheese or persons. “We don’t have the foggiest idea of how metaphors work,” says the neuroscientist Ramachandran, “or how they are represented in the brain.” (79). He is optimistic that a scientific understanding of the neural basis for synesthesia might illuminate how metaphors are represented in the brain and how we humans have evolved to entertain such expressions in the first place. Neuroscience might help to unlock a key feature of our existence as rational and language-using beings.
So the riddle of metaphors and the brain makes me wonder, as a humanist, whether Waliyullah’s explanations imply that the brain is also culturally wired. And, if so, then what about claims that the brain is a closed system? And, if it remains a closed system, then how does the culture seep into it?