Question

How many commentaries have there been of the Nyaya Sutras?

Answer

I know of six commentaries on Gautama's Nyaya Sutras:

  1. Vatsyayana's Nyaya Sutra Bhashya, which you can read here.
  2. Uddyotakara's Vartika on Vatsyayana's Bhashya, which you can read in four volumes here, here, here, and here.
  3. Vachaspati Mishra's Tatparya Tika on Uddyotaraka's Vartika, which isn't available in English, but is available in Sanskrit here.
  4. Udayana's Parishuddhi on Vachaspati Mishra's Tatparya Tika, which isn't available in English, but is available in Sanskrit here.
  5. Raghunatha Shiromani's Bhashya Chandra, which isn't available in English, but is available in Sanskrit here.
  6. Vishwantha's Nyaya Sutra Vritti, which you can read here.

One note of caution: not all these commentators are actual members of the Nyaya school. Vatsyayana and Uddyotakara were Naiyayikas, but Vachaspati Mishra was an Advaitin, and Udayana and Raghunatha Shiromani were members of the Navya Nyaya school, which was a fusion of Nyaya and Vaisheshika. The original Nyaya school died out around the 12th century, so all commentators after that were from outside the Nyaya school.

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