The accuracy of these indexes is dependent on multiple factors:
The accuracy, consistency and completeness of Bhikkhu Sujato's translations found on the Sutta Central website. Bhikkhu Sujato seems to have done a very good job with the first two of these, but I cannot say anything more than "seems." As for completeness, this is by far the most complete English translation of the Buddha's discourses. But even then, there are shortcomings. Some suttas have ellipses - far fewer than most other (and incomplete) collections, but they do present a problem when trying to find ALL the suttas for a topic. For example, the first version of the "Mindfulness" index was missing 6 of the first 13 suttas in the Digha Nikāya because the section on mindfulness used ellipses which resulted in the "mindfulness & situational awareness" topic not appearing in DN 4, 5, 7, 11, 12 and 13. These links were added manually, but it is unknown if there are similar cases for "mindfulness" or any other search terms. So completeness is always going to be a problem - unless an index is manually checked, which I do occasionally do.
Possible bugs in the Unicode Document Processor. It is a very powerful program for doing things like this. But I am the programmer AND the tester - a bad combination. All programs need to be tested by people other than the authors!
My choice of search terms for doing the selecting. I find what term(s) Sujato used to translate a Pali concept, and can select based on multiple terms being used by the Buddha (e.g. "emptiness" or "empty" for the Emptiness index). But some words are used in multiple contexts (e.g. "emptiness" or "empty" for the Emptiness index but that also includes "empty room", "empty hut", etc. and these must be removed in subsequent steps). Some words are used in many multiple contexts.
Because of this, I have given a rating to each index:
****
Probably complete and manually checked to removed any extras
***
Probably complete but Not manually checked to removed any extras
**
Maybe complete? Not manually checked to removed any extras
*
Known to be incomplete and/or known to contain extras
Sutta references without names are because there was no name given for the sutta in the Sutta Central website. When possible, I have included the first words of the sutta to give a possible hint of what the sutta is about but at times even this was not possible - e.g. because of the automated nature of generating these indexes, the Dhammapada references have no further information.
If there are quotes in an index's name, that was the search/select term. If there are no quotes, the the name of the index and search/select term are the same.
The number of suttas or number of sutta links in an index is based on the lines in the generated index. Some lines cover multiple suttas - e.g. "Emptiness" includes AN 3.183-352. But those suttas only reference "Emptiness immersion" and aren't really teachings on emptiness. So should that be counted as 170 suttas? I think not, but I left the reference in since that index is of all the occupancies of "emptiness"; hence I document 17 Sutta Links instead of 186 Suttas. When it says "## Suttas," the actual number of suttas is given; but if there are many links that cover multiple suttas or links that point to highly repetitious suttas, I only give the number of links as "## Sutta Links."
Use these indexes as a starting point - not as a final word on anything.
Leigh Brasington
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/ Revised 20 Oct 24