Limits of sense perception

Teaching heat transfer to students the topic of Thermal Radiation and electromagnetic radiation in general brought to mind the limitations of perception.

Although we take the colors we see as 'objective truth' to the extent that we would be upset if our laundry or dry cleaning failed to remove some stains on our clothing, when we understand the science of radiation and color perception, it rapidly becomes clear that color is not intrinsic to any object. It is merely the absorptive properties of the material that make it absorb all wavelengths of radiation incident on it, other than the frequency band that corresponds to the color we ascribe to it.

So the first thing we learn from this important scientific fact, is that we are not seeing a lot of the spectrum of radiation itself. In other words, our perception is very limited. When we see objects through infrared imaging they look very different because in that frequency band it is the temperature of the object that determines its 'color'. Now that infrared image has to be converted to a 'false color' for us to see it. And yet, how much blind faith we have in 'seeing is believing'. How dead sure we are that we saw so and so do this, or someone in that color car get away from the scene of the crime! Of course this all has its place in the empirical dealings with the phenomenal world, but the true sAdhaka should ponder on this limited perception.

The second important point to take away is that, different people perceive the same object differently. The whole issue of color blindness is exactly about this. This should really make us question the assumption in classical science that the object has some 'reality' that is independent of the observer (quantum physics does take some steps to remedy this, but I am not an expert in that subject beyond a rudimentary understanding of Heisenberg's uncertainty principle that brings in the role of the observer in experiments). In fact, this is what Yoga Science has been saying from times immemorial: that the object perceived is not independent of the observer, but is colored by the observer's mind. In fact, the object has no existence outside the mind of the observer, something that Zen Buddhism also points to through its koans.

Consider how unreliable the senses are. SwamiJ's website had an interesting article on synaesthesia that is a condition where the sense channels get mixed up so people can feel colors, and so on. Within the same species our sense perceptions are not invariant and consistent. Even when a 'normal' person has a common cold you can quickly tell that your sense of taste is strongly affected if your sense of  smell is impacted. So there is a small level of synaesthesia between the gustatory and olfactory perceptions even for so-called 'normal' people.

So what we call "normal perception" that is commonly agreed on in society is only a "coherent madness" in my opinion. This alone should alter our perception on 'race relations' and the notion of color in society.

If we consider other species such as dogs, science tells us that they hear and see differently.
So, perception is not of one objective reality but even species specific.

For a sAdhaka, one of the main lessons to take away from this is that affirming the false objective reality by conventional speech is dangerous and highly counter-productive to jnAna. Hence the great deal of emphasis placed on mounam (silence of speech but more importantly mind), and caution against engaging in prajalpah (gossip).

It is bad enough if during the course of conversations in the external world we have to restrain the senses and be aware of the Self by not seeing the difference between one and the other. Two are bad enough, but gossip is the worst because it gives false reality to a third non-existent object that really deviates the mind from the Self.

No doubt all of this will sound like madness to the unawakened. Cf. the Bhagavad GItA says YA nishA etc

Therefore, in the HaTha Yoga PradIpikA, SvAtmArAma says to keep the secrets of Yoga, gupta (or secret) and to appear ignorant for sake of appearances.

In summary, the mind is nothing but a bundle of habits. Even the perception of good food is also a habit. It can be changed. But sattvic food helps the mind see through the fakery and brings it to the first mahAvAkya: Brahman satyam jaganmithyA (The Self is Real, the world is Unreal).