Well, I would say that jhana results in samadhi. There are other examples in the sutras. One that I recall well is the exchange in the Parinirvana Sutra with Pukkusa when the Buddha relates a time when he sat through a lightning storm and didnât hear or see any of it because he was in meditation. When heâs asked if he was conscious (saññī) at the time, he replied that he was. He told that story after Pukkusa tells the story of Alara Kalama sitting through a five hundred cart convoy rumbling by next to him without noticing it.
At the conscious level of vijnana. There is no conscious awareness of something if vijnana isnât giving it attention. Sanna is not this function of awareness; itâs a tool that vijnana uses to recognize things. It processes raw input from the senses into concepts and imagery. The word is often used for those concepts and images, not just the function of mind that creates them.
But conscious awareness is vijnana, and itâs attention directed at a small portion of the sensory field at any given moment. We become aware of where we direct our attention, but it floats around freely from one sense to another when we arenât focused on something, which gives the impression of being aware of everything at once. When attention first lands on something, the initial experience is vitakka. If it stays there and examines it, thatâs vicara. Most exegesis characterize vitakka as initial and crude, and vicara as subsequent and increasingly refined, like the sound of a bell.
The concrete example of this I like to use is seeing an animal run across a footpath. In the initial moment of recognizing it, itâs mostly a blur. It has a vague size and color, maybe we notice that itâs furry or scaly. But it takes a moment or two of attention to recognize that itâs a squirrel or a lizard. Longer than that to recognize what particular species of squirrel or lizard that it is (which also requires knowing how to identify the species). The animal will need to stop in front of us long enough to do that. But itâs quite possible to not even notice the animal at all. We have to actually give it that initial attention or recognition to be aware of it.
Iâll give another example thatâs clearer: Sometimes while Iâm concentrating on translating Chinese, my wife appears in my doorway and starts talking to me. Now, I do notice that sheâs standing there and talking, but if I donât stop working and give her my full attention, I wonât âhearâ anything that sheâs saying to me. Which, embarrassingly, happens sometimes. When I realize, âOh, I didnât hear any of that,â I stop and ask her to repeat herself. Sheâs standing two feet away from me, and I have excellent hearing. But Iâm stuck in visual and mental vijnana in front of a computer and not paying much attention to what Iâm hearing. I.e., Iâm not aware of the actual words being said. Thereâs only a vague awareness of someone talking. The Buddhist way of thinking about it is that my attention doesnât stay on what Iâm hearing long enough to recognize words. Itâs skipping back and forth, staying mostly on what I was doing before she arrived, so there is only a vague awareness of the situation.
In these examples, sanna is not the awareness of something, but the image thatâs formed immediately upon sensing it. That image is matched to what we already have experienced or learned. Recognition takes place when the closest match is made, and the concept that it matches usually has a verbal name. In the footpath example, it might be âred squirrel,â though maybe at first itâs just âanimal.â There would probably be multiple matches happening in quick succession: Itâs an âanimal,â then a âmammal,â then a âsquirrel,â then a âred squirrel,â maybe it even reaches the level of âan adult female red squirrel thatâs well-fed and healthy-looking.â It takes time for that to process of refined recognition to happen. This is what vicara describes. Like the sound of the bell, it becomes more and more fine.
An easier way to notice the unconscious sanna process is when it goes wrong. Sometimes, the sensory image is matched to the wrong concept in our memory, and itâs confused for something else. The wrong thing replaces it in our experience, becoming like an hallucination. I remember a time when I was driving at night and saw a piece of farm equipment in front of me, lit up with a bunch of lights. It was too dark to see itâs shape. For a few seconds, what I âsawâ was a UFO hovering over the road. Thereâs also the traditional example in ancient texts about mistaking a rope for a snake. Usually, those hallucinations donât last very long, but they happen. It indicates that thereâs an unconscious process of sanna-making, but weâre only aware of itâs end result. Vijnana isnât directly aware of raw sensory data; it works with the sanna thatâs formed from it.
This is how I understand the use of these words, at least. Itâs largely a generalization of how they were used by various Buddhist traditions, so itâs likely to not entirely agree with any one in particular.