Consciousness is Mara [the evil one]. — Samyutta-Nikaya
Just recently, I have been giving a great deal of thought on the difference of vijnana from our translation of it with ‘consciousness’. The rendering of consciousness for vijnana is just an approximation. The latter doesn’t include all vijnana suggests. What is missing, in my view, which is an extraordinary insight on the part of the ancient Hindu mind, is that vijnana can also refer to the faculty of validity (I am still not happy with the term ‘validity’ but for now it will have to suffice). In simple words: whatever vijnana shines upon it makes it seem real which might be a dream or our everyday life—or even a mere thought. In also needs to be kept in mind that validity is not the same as truth (satya). Truth is ever beyond consciousness.
In the example of the Twelve Nidanas (nidâ, lit., to bind down thus ‘bindings’) beginning with ignorance (avidya) and ending with old age and death (jaramarana), vijnana/consciousness (the third nidana) gives the highest validity to name and form (namarupa) which is the fourth nidana. In the case of rebirth, vijnana, so to speak, shines on the fertilized ovum (namarupa). As a result, vijnana continually validates this human cellular existence giving it the sheen of true reality. But in so doing it becomes deeply embodied and individuated (satkaya) from whence arises our sense of personality.
Another illustration, turning to the so-called practice of ‘conscious dreaming’, we underscore the fact that vijnana imbues the dreamscape with validity so that the dream seems quite real. This is so with any psychosis.
As regards the use of drugs, the altered state of perception is, again, validated by vijnana so that the euphoria which is experienced seems real enough. As a result, one is subject to becoming addicted—only because vijnana validates the drug-induced perception of reality.
As the reader can surmise, vijnana/consciousness is quite powerful. It can even validate the false, making the false seem to be the truth. Just as much, it can make an absurd belief seem otherwise important and necessary. Yet, vijnana is not the highest point. Far from it. What is valid is not necessarily true. This, by the way, is why Western knowledge, including its religions, will ultimately fail. Both are dependent upon the validating effect of consciousness (vijnana).
In the West, consciousness is trained to fixate on the sensory organs and their respective fields thus validating their data. This stems from the long standing belief that what the senses perceive is fairly true. However, it is not. It is the field of the unconscious where the road to the true is to be found. This is why the way of Zen can seem to be so paradoxical for many people.