The Medieval Shroud 2 begins with a discussion about pareidolia which I think has been widely misunderstood, entirely due to my own extension of the meaning of the word further into general perception than was popularly warranted, and insufficient explanation of what I had extended it to mean. Let me clarify.
Pareidolia is usually defined as the tendency to see meaningful images in random shapes, such as elephants in clouds or Jesus on a piece of toast. However I’m afraid I broadened this to consider pareidolia to mean our more general innate tendency to derive more information about our surroundings than is supplied by sensory evidence. If we see the top half of a man above a desk, we assume that in fact a whole man is sitting or standing behind the desk, supplying from our experience some information about the man that is not directly given by our vision. If the same man rises and walks away, we recognise that he is not really getting smaller and smaller, although our vision shows us that he is. In the first case, experience adds to stimulus, and in the second, actually overrides it. In the image below, most people recognise a white triangle overlying a black-edged triangle and three black discs, their brains not only completing the edges of the white triangle, which would be visible if it really existed, but even the missing segments of the other triangle, and the discs, which wouldn’t.*
The images below are easily recognisable as people, and, to many readers, as actual individuals, although the sensory stimulus is minimal.
What’s more, in recognising the individuals, we may even find one image more attractive than the other, one perhaps invoking feelings of nobility and patriotism and the other of risibility and disgust.
The illustration below gives us an interesting development of this theme, in that two images are presented, one the inverse of the other. They both contain, visually, exactly the same information.
However, although there is nothing in the second image that is not present in the first, we immediately recognise it, whereas the first is meaningless. This is because we can relate the patterns of light and dark in the second to previous experience, but not those of the first. Furthermore, again using previous experience, we may perceive three dimensional information, such as the contours of the nose and cheeks, or the eyes in the shadow of the brows. Depending on our cultural heritage or education, we may go further still and identify majesty, wisdom and authority.
The Shroud is comparable, if considerably more refined.
In this case, of course, the first image is certainly not unrecognisable in itself, but there is no doubt that the second seems to tell us a great deal more about the person portrayed, even though there is no more information in it. The eyes are often described as ‘owlish’ and open in the first, but are apparently clearly closed and not unduly exaggerated in the second. The swell of the lower lip, the protrusion of the nose and depth of the cheeks all seem clearer and more ‘realistic’ in the negative image, and of course the cultural associations of a God in repose are more easily interpreted there than in the ‘positive’.
There is an argument that our understanding of any representative image is in some ways pareidolia, as we are bound to derive some extra information about what is represented from our previous experience, however detailed and informative the image. A picture of a man in a suit of armour or a Hawaiian shirt conjures up a context of time and place, although the image does not in itself suggest any such things. Every interpretation of an image has a ‘sensory’ and an ‘experiential’ component, and an attribution of pareidolia relies on the relative proportions of the two.
Without juggling further with semantics, I think the point about the Shroud is that some devotees have insisted that the ‘negative’ literally contains more information than the ‘positive’, which it doesn’t. Confusing what we derive immediately from our senses with what we derive from our experience is exactly the point of contention, as although normally sighted people will ‘see’ with their retinas exactly the same image, they may ‘see’ with their frontal lobes something quite different from each other. Thus to many devotees the image is so exactly perfect that it cannot be the result of artifice, while to non-authenticists it is sufficiently unrealistic for a manufactured provenance to be reasonable. It was my intention to initiate an argument that the ‘perfect’ interpretation is unjustified, and due more to pareidolia than observation. Explaining how and why will follow in a separate post.
*Illusions: 1) Kanizsa Triangle: Kanizsa, Gaetano. ‘Margini Quasi-percettivi in Campi con Stimolazione Omogenea’, Rivista di Psicologia, Vol 49, 1955. 2) Lincoln: Harmon, L.D.,’Some Aspects of Recognition of Human Faces’, Fourth Kybernetic Kongress, Berlin, Springer, 1970. 3) Hitler: Unknown. 4) Jesus: Unknown