The translators of the Hridaya [‘Heart’] Sūtra had struck gold with the pick of the English word to translate Shūnyathā by reaching into the vocabulary of Classical Logic.
But they were flailing around, understandably, for an equivalent choice for the term Nāmarūpa. In fact by this time its interpretation in the Sanskrit itself had become entirely flaccid.
Then the Translators noticed the English word ‘Form’ which happened to be part of the extended vocabulary of Classical Logic. It had a nice ring to it and the meaning appeared very close to the word Nāmarūpa. And so they went with ‘Form’, a palliative compromise. [The word first appears in Plato’s ‘Theory of Forms’ which is probably where it was noticed.]
Nāmarūpa, an assertive noun is about the closest conventional term you will find to the free, open-ended negation: ‘Not-True Nothing’. But as a translated term, it gets even more nuanced.
But Nāmarūpa is not exactly ‘Form’, and the two words are not perfect translation matches. For Nāmarūpa has a seriously slippery feature to it: Self-Reference.
‘Form’ as commonly used in Classical Logic is: ‘Something that is marked, has taken shape’. A line, a curve, a color, a smell, a melody, a scratch. Logic comes alive, is operative, only in the abstract, only in the world of Form.
But Nāmarūpa does not exactly overlap with the ‘Form’ as defined by the Logician. Nāmarūpa like Form, is ‘Something that is marked, has taken shape’. But Nāmarūpa, unlike the Logician’s Form, an ‘Objective’ presence, includes within its domain all ‘Subjective’ presence’ as well.
Feeling is Nāmarūpa, a mental-image is Nāmarūpa, internal-dialogue is Nāmarūpa. All that you see with your eyes closed or hear with your ears plugged are part of Nāmarūpa. If you can name it, mark it, express it, put a metaphorical finger on it, it is part of Nāmarūpa.
All references to Nāmarūpa are already contained in Nāmarūpa as are all thoughts you have in response to it. If you slip on its self-referential feature you will confound Nāmarūpa with Awareness, Consciousness, Presence, World and other such heavy concepts, all of which are equally misleading.
[Next time a book-read teacher goes on about how ‘Form is Emptiness and Emptiness, Form’, do the class a favor and stop him in his tracks.]