What is real? The easy answer to give would be 'everything'! Surely? Also to say otherwise could be denying another's experience, and that's not cool in my book. Maybe a better way to think of it is, where is this 'reality' created, and is this 'reality' real?
I will talk briefly about sight as it is the most widely researched sense in Western science, and for most of us the main sense we use. It also takes up the most 'processing power'. It might seem something we do not ‘learn’ how to perform, as those who are able-sighted will possibly perceive the sense of sight to be an easy and automated process. It would be assumed that we see is what is real, and an exact copy of the world, which seems full of information and seamless. Unless we are shown otherwise, this seems to be cognitively correct. But is this true?
There is much evidence of actually learning ‘seeing’ (eg. Duffy & Mitchell, 2013; Huberman et al., 2006), with Hebbian plasticity apparent. For example, Huberman et al. (2003) in their experiments on developing ferrets, discovered spontaneous waves created a segregation of left and right eye inputs in the dorsal lateral geniculate nucleus (dLGN), which when blocked using immunotoxin depletion of starburst amacrine cells became intermingled. This showed that when these inputs were unsynchronised, there was a plasticity involving long-term propagation and depression in the dLGN to create zones for each eye. What this really means is that we are learning to see, even before we open our eyes, so it's no wonder we have no idea we've learnt this skill.
Now whilst vision may feel pretty automated, it is in fact hierarchical system, starting in the primary visual cortex- V1- with simple dots and lines and the picture further developed with other areas of the occipital cortex along two streams- ventral and dorsal- to depict what and where respectively. These streams are evident in impairments such as visual agnosia, as studied by Karnath et al. (2009). The ishemic stroke patient they studied could not identify everyday objects, yet could safely walk around the neighbourhood and objects could be identified if using haptic information. The stroke had affected medial aspects of the ventral occipitotemporal cortex, which is necessary for shape and contour information, and demonstrated the existence of the ‘what’ stream. The hierarchal nature of the streams was demonstrated by the patient still being able to see colour, which is processed in V1 and V2 (Gegenfurtner, 2003).
Our perception of how we see the world in complete colour is a complete misconception too. There are three types of cone photoreceptor in our eye to give trichromatic vision (Solomon & Lennie, 2007), but Marshall and Arikawa (2014) discovered creatures- such as the stomatopod- which had 12 types of cone photoreceptor, giving a greater spectral sensitivity- 300-750nm- than found in humans- 400-700nm. Whilst it is impossible to imagine, this means we are not seeing all that there is. We may not perceive it, but there is also a loss of colour information in the peripheral visual field, demonstrated in Abrahov and Gordon’s study (1976), testing the spectral sensitivity of their subjects at 45 degrees from the fovea. Whilst this is thought to be due to the location of the cones in the forvea, it may also be due to post-retinal mechanisms (Martin et al.,2001).
Humans are also susceptible to what is called change blindness, where changes in what we are looking at are not perceived. Whilst various studies have observed this phenomenon, giving reasons such as visual memory, (eg. Pashler, 1988) and saccade-specific mechanisms (eg. Currie et al., 1995), Rensink et al.,(1997) attribute this to memory. They created a flicker paradigm, by placing a blank image between successive modified images. This blank image effectively sent motion signals due to be entirely different, and then attention was drawn from the area of change. In a further experiment, cues were added to test whether the change blindness was due to attention or because the flicker made it difficult to see. The results suggested that we only perceive change when that object is given attention, otherwise the visual memory is replaced by the next stimuli. It has since been discovered by de Shotten et al. (2011) that the three branches superior longitudinal fasciculus (SLF) provide a network for visuospatial attention and communicates between the dorsal and ventral networks. Using a line bisection test they found that participants deviated to the left, and those with larger SLF II volumes on the right hemisphere showing greater deviation. The results demonstrated an asymmetrical processing of visual scenes and an unbalanced speed of visuospatial processing.
There are many other ways it has been demonstrated by Western science that what we think we see, isn't actually the 'reality'. Well guess what, yoga was way ahead of us on this one. So what does yoga say?
All is māyā. That is all is 'illusion'. Quite often I've just heard that be shared, with little further explanation. I've also received further explanation and ended up in some dark, dark holes- try the never ending circle of 'yoga teaches that all is māyā, but then is also that māyā, so what is effing real and true?' Nobody needs to go through that (although maybe it's necessary too in order to gain insight...I don't know the route of your path)!
First of all there's no need to panic here. I primarily write to spark interest and intrigue in the teachings, which fear won't ever give! To unpack them fully cannot occur in a blog post, so this is somewhat a little look at the 'menu', without really being able to tase any of the 'dishes'. Although perhaps you've already tasted some of them.
Have a little look below. Tantra philosophy describes 36 elements- tattvas- which make up the universe, in order from the grossest to the subtlest. . Many of the gross elements you'll already be aware of so I have missed them out here (eg the element of earth- prithvī). It starts to get interesting (in my opinion) from manas- the mind- upwards.
We've already seen that our brain is making up what we see. We perceive through the five organs of cognition (pañca jnanendriyas) seen at the bottom of the 'menu'. What is perceived is translated by our three internal organs- mind, intellect and ego, which form puruṣa- our individual consciousness. With this we are able to witness māyā. Do not let the fact it's an 'illusion' put you off here. It is the subtlest element before experiencing univeral consciousnes, known as a covering- kañcuka.
We have six of these coverings (including māyā herself) which are said to be 'bondages' to the human bodily experience. Ultimately these cause us separation when our understanding is 'limited' and create 'the illusion of individuality'. Why? Because with 'limited understanding' we are essentially 'looking down' the tattvas, experiencing the grossest elements. Yet this māyā also gives us the chance to focus 'upwards'. In other words, māyā is the cause of suffering, but can also be the route of liberation. As Swami Laksmanjoo states:
You won't find the real state of Lord Śiva in samādhi. In the state of samādhi you will find his non vivid formation. You will find the exact state of Lord Śiva in the Universe.
We actually experience this often in our lives, without realising it. Abhinava Gupta talks of 'aesthetics' as a means of perceiving the divine. So those times you look at something and the beauty literally takes your breath away. Time stands still and then after an unknown amount of time, thinking occurs and we move back 'down' the elements. You have witnessed beyond the illusion in those moments! Notice where the element of the mind is. Grosser than māyā. This is why Swami Laksmanjoo says 'just try to see that non understanding state [and] you will get entry in God consciousness.' Don't let the 'G' word trigger, but think back to the experience of real beauty- it is that.
The thinking mind serves a great purpose in helping us along the way. With the teachings of yoga we are really replacing one form of buddhiḥ ('limited understanding') with another (we'll call 'spiritual understanding'). Yet the attachment to the mind is one of the coverings- vidyā so there comes a time we simply have to experience. There are numerous ways to experience what has been given many names, but most commonly the Self. In the 'Vijñana Bhairava', 112 methods/meditations are given. Don't expect them to be all just sitting in meditation. One of my favourites is verse 66 which is tickling! It turns out I thought my mum was trying to torture me as a child, but she was simply trying to elevate my consciousness! Thanks mum.
I hope that this has revealed a little of the depths of yoga and given inspiration to learn more. I am always available to offer advice on books and great teachers, as well as offering some of my own limited understanding. I will expand upon points in time, but there is no rush. That's just the cloak of kāla!
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