(this may seem afield, but does come back to nimitta)Dmytro wrote: ... an inner representation of the object that one has acquired previously
Brings to mind the neurological hypotheses of Antonio Damasio ("Self Comes to Mind: Constructing the Conscious Brain" 2010) as to how images, representations are apprehended, stored, and recalled. Specifically the point that though the brain creates picture-like mappings from sensory input (and all 6 senses), these are stored (as processed, "perceived", i.e. sanna-like) not as literal, so to speak, bit-maps, but rather as a combination of some aspects of the data AND aspects of the experiential process that accompanied the acquisition of that which gets stored. So recall is actually a replay of the algorithm, so to speak, of the original event.
(Btw: This and several other tantalizing ideas / hypotheses in Damasio's book lead me to suspect that if he had been born in a particular distant age, he would have been an "Abhidhammiker"; for that matter, perhaps he was once born so. And, of course, he does deal with "qualia".)
1) Perhaps the slavewoman of Raṭṭhapāla's family wasn't just recognizing pictorial images, so to speak, of his features and vocal tone, but also the manner of his behavior. We can probably recognize this in "recognition", especially those of us with some age under the belt – meeting someone from high-school at the 50th reunion, the appearance may be rather unexpectedly strange, but then the vocal and other behavior help tease out the memory and make recall connections.
2) I would argue tentative experiential evidence of such: Namely when having a well-developed sense of nimitta that can occur in achieving anapanasati-samadhi. Recalling this, with further practice, it becomes progressively easier and quicker to attain absorption – not just because the "image" is sharper or what-not, but because it includes recall of the mental activity, behavior of entering jhana – how the "path" of it is to be traversed. (This might apply generally – recall in performing music, of how to ride a bicycle,…)
In the linguistic analysis, is it possible to detect any analogous relationship between the nominal and verbal aspects (both the "picture" and the "play" so to speak) in the term "nimitta"?
The verbal aspect has been at least implicit so far – as in Dmytro's "This apprehension is a controllable mental act…", where (perhaps) the ontological bias of our language uses the noun "act" to refer to what's in vivo an "acting". Also, the vedana aspects (clinging khandhas) that can so strongly associate are inclinations to acting-out.
(Damasio's radical hypothesis, back in the 1970's, that "consciousness" arose (in evolution) / arises from, originates with "emotions", by which he means what we know as the vedana – from the most primitive level of organism, e-moting (Latin: "moving-out") with attraction to potential food, or with aversion to potential predator/eater. That hypothesis was ridiculed in the science world back then, but was experimentally verified in the 1990's.)