After a short time of the enlightenment the Lord Buddha had the unique ability of preaching his doctrine in such a way that everybody understood. He used different methods to preach His Dhamma. The four methods are explained in the commentary to the Anguttara Nikaya, and the Abhidhamma. The four methods are as follows:

  1. Ekansa Vyakarana – question which ought to be explained categorically.
  1. Vbhajja Vyakarana – question which ought to be explained analytically.
  1. Patipacca Vyakarana – question which ought to be replied with a counter question.
  1. Tapaniya – question that should be set aside.

* Last method:

Here the last method (Tapaniya) explains questions that The Buddha did not answer (Avyakruta). The Buddha declared certain questions of distinctly metaphysical character to be unanswerable. It is necessary that the silence of the Buddha should be properly appraised. The inexpressible (Avyakruta) occurs in many dialogues.There are only ten but invariably enumerate as fourteen and practically is The same order. Avyakruta are explained in the Vaccayotta Sanyutta and Avyakata Sanyutta of Sanyutta Nikaya, Mahanidana Sutta, Brahmajala Sutta, Mahali Sutta and Pottapada Sutta of Diganikaya. These are the ten unanswered questions.

  1. Sassato loko – The world is eternal.
  2. Assato loko – The world is not eternal.
  3. Antava loko – The world is finite.
  4. Anantava loko – The world is Infinite.
  5. Tanjivantana sariran – The soul is identical with the body.
  6. Annancajivan annam sariram – The soul is different from the body.
  7. Hotitatagato parammaranan – The Tathagata exists after death.
  8. Na, hotitathagato Parammaranan The Thatagata does not exist after death.
  9. Hotica, na hotica Tathagato Parammaranan – The Tathagata does and does not exist after death.
  10. Neva hotica Nanahotica Tathagato – Parammaranan – The Tathagata neither exists or does not exist after death.

* First four questions

Here, the first four questions are about the world. Fifth and sixth questions have been asked regarding the soul and the body and the last four questions are about the saint (Tathagata).The Buddha has said that these metaphysical questions should not be investigated by man because they are – unfathomable questions regarding this reason.

some western scholars believed that The Buddha did not know the answers for this question. It should be noted here that Radhakrinan has rejected the comment of A.B. Keith and said that The Buddha knew the answers but did not express them because it is not important to realize the salvation which He has taught.

*Two questions :

Now, two questions arise

(i) whether, The Buddha had known or not known the answers for these questions

(ii). If He knew the answers, why did he set aside these questions?

The answer for the first question can be found in the Simsapa Sutta of Sanyuttanikaya. Here the Buddha himself explains using some simsapa leaves. The Buddha takes a handful of the leaves in the simsapa forest and says that what he has taught is like the leaves in His hand and what he knew but did not teach is like the leaves in the forest (eva mevakho bhikkhave etadevabahutarani yan kho pana maya abhinnaya anakkhatan).This means that he claimed to know much more than he taught.

Second question

The answer to the second question or the reason to set aside these ten unanswered questions, has been explained in the Pottapada Sutta of Majjima Nikaya. According to that Sutta the Buddha has explained to Pottapada that answers for these questions are not important to cessation of suffering and to realise the Nibbana. Therefore the Buddha has set aside these questions. (Netan atta sanhitan Na dhamma sanhitan… na nibbanaya, san vattati, tasma tan maya avyakatan).

Further, He explains in Vaccagotta Sutta of Sanyutta Nikaya The reason for setting aside these questions. There the Lord Buddha tells Ananda, why Vaccayotta was answered by ‘silence.’ When I was asked by the wanders, whether there was a self? I replied to him that there was a self, Ananda, that would be siding with the recluses and Brahamins who are eternalists.” But Ananda, when I was asked ‘Isn’t there a self?’ I replied that it did not exist. Ananda, that would be siding with those recluses and Brahamins, who are annihilationists. Again, Ananda, was asked by the wanderer, ‘Is there a self?’ Had I replied that there was a self it would be in accordance With the knowledge, all things are impermanant? Then Ven. Ananda answered it as, “Surely, not Lord.” Again Ananda, when Vaccagotta asked, “Isn’t there a self. I replied that there was not. It would have been more bewildering to the already bewildered Vaccagotta. The Buddha says, ‘Ananda’, If I had answered the questions with ‘yes’ or ‘no’, or accepted one of the alternatives I would have been guilty of that very dogmatism which he had been vehemently condemned by others.

Instead of the usual opposition, between Sassatavada and Uccedavada (affirmation and negation) The Buddha substituted the more fundamental one between dogmatism and criticism. The Buddha has said to the Kaccayana in Sanyuttanikaya, how He preached the doctrines: “Kaccayana affirmation is one stream, negation is the other stream. Tathagata preaches His doctrine without grasping both these streams.”

( “Sabban attiti bho kaccayana ayan meko anto, Sabban nattiti bho kaccayana ayan dutiyo anto,

Ete vbho ante anupagamma majjimena Tatagato Dhamman deseti.” ) This is his middle position. The Buddha has kept his noble silence without answering the metaphysical questions.

May all beings be well & happy and attain the fruits of Nibbana.