Perceptual diversity and philosophical belief

In Reasons and Persons Derek Parfit formulates the view that personal identity is reducible to physical and psychological continuity of mental states, and that there is no ‘further fact’, diachronic entity, or essence that determines identity. The belief that persons are separate entities with continuously existing selves, he argues, is to a great degree an illusion. The New Yorker profile only fleetingly connects Parfit’s philosophy to his aphantasia, but to me it seems an obviously relevant piece of explanation. Our philosophical views are based on our intuitions; our perceptual experience of the world guides our ideas about it. 
Likewise, my own aphantasia could at least in part explain my intellectual preference for and easy identification with non-essential conceptions of self in both Western philosophy and Buddhism. The question is, then, whether the condition of aphantasia gives people like Parfit and me a shortcut to enlightenment and clearer philosophical insight into and intuitive understanding of the human condition and nature of reality. Or, does it obscure the truth by barring us from dimensions that are integral to the most common human experience and installing intuitions that do not correspond to the norm?
The growing insight into perceptual diversity, then, gives way to an increased possibility of biographically understanding and explaining philosophers’ theories and as such allows for a new form of ‘neuro-biographical’ reading of philosophy. 
“He has few memories of his past, and he almost never thinks about it, although his memory for other things is very good. He attributes this to his inability to form mental images. Although he recognizes familiar things when he sees them, he cannot call up images of them afterward in his head: he cannot visualize even so simple an image as a flag; he cannot, when he is away, recall his wife’s face. (This condition is rare but not unheard of; it has been proposed that it is more common in people who think in abstractions.) He has always believed that this is why he never thinks about his childhood. He imagines other people, in quiet moments, playing their memories in their heads like wonderful old movies, whereas his few memories are stored as propositions, as sentences, with none of the vividness of a picture.”
As I was soon to find out, however, the absence of a visual component to Parfit’s imagination is part of a neurological condition which affects an estimated 2-5% of the population, including myself, namely aphantasia. 
As neuroscience and neurotechnology continue to develop and give us better understanding of the variations and differences in the neurological constitution of brains, it will be interesting to see to how far the awareness of perceptual differences and specificity can reach in the explanation of differences in philosophical intuitions and beliefs – and to what extent it can disqualify philosophical positions and theories. The notion of perceptual diversity offers a valuable route for philosophers to exercise self-criticism, scrutinise their theories and intuitions and investigate the underlying perceptions and experiences. At the same time, it troubles some of the fundamental concepts on which the discipline of philosophy relies, paving the way for further relativisation and destabilisation of the already undermined notion of objective truth and rationality and potentially removing us further from consensus.
Surely, Parfit’s experience would be representative of the norm, I thought  – i.e. to only be able to see things that are actually there, physically present and immediately visible in the external surroundings? I certainly never had this seeming super-power of creating images myself and had always assumed that my subjective experience corresponded to the average. 
As modern neuroscience is giving us deeper insight into the wide neuro- and perceptual diversity of people, it is also giving us new explanations of differences in people’s experience of reality and, accordingly, their philosophical intuitions and beliefs. According to the predictive processing theory of brain function, the reality we experience as objective and independently existing, is to a large degree created by our brain, a projection based on our brain’s best guesses about the external reality and as such a form of controlled hallucination. And as Anil Seth has recently pointed out, since we all have different brains, we will naturally make different guesses about the external reality we encounter and thus have different perceptual experiences of reality. “Just as it serves us well to occasionally question our social and political beliefs, it’s useful to know that others can literally see things differently to us, and that these differences may evolve into different beliefs and behaviours.”


In addition to these, I think aphantasia is likely connected to a certain philosophical belief or position, namely the non-essentialist view of the self that is found in both the reductionist account of personal identity in Western philosophy and the no-self doctrine in Eastern contemplative traditions. I offer a more extensive argument for this connection here: https://psyche.co/ideas/aphantasia-can-be-a-gift-to-philosophers-and-critics-like-me.
Recent studies into aphantasia (e.g. https://pubmed.ncbi.nlm.nih.gov/34296179/) connect it to a number of characteristics and personality traits, including introversion and autistic spectrum features, difficulty with recognition, including face-recognition, impoverished autobiographical memory and less event detail in general memory, difficulty with atemporal and future-directed imagination, including difficulties with projecting oneself into mentally constructed scenes and the future, reduced mind-wandering tendency, elevated levels of IQ and mathematical and scientific occupations. 
Reading up on Derek Parfit’s theory of personal identity as part of my research on non-essential accounts of self in literature, philosophy and neuroscience, I was astounded to come across a New Yorker feature on the philosopher which describes his inability to visualise imagery as an anomaly:
It seems plausible that the flipside of a reduced sense of the past and future is an increased connection to and absorption in the present and a weaker identification with a continuous personal narrative and a coherent and substantial self. Parfit’s diminished sense of continuity of identity and substantiality of his own self – which he himself explicitly links to his aphantasia – may well have led him towards or at least strengthened his anti-essential views of personhood.