"A man approached the Blessed One and wanted to have all his philosophical questions answered before he would practice. In response, the Buddha said, It is as if a man had been wounded by a poisoned arrow and when attended to by a physician were to say, I will not allow you to remove this arrow until I have learned the caste, the age, the occupation, the birthplace, an...d the motivation of the person who wounded me. That man would die before having learned all this. In exactly the same way, anyone who should say, I will not follow the teaching of the Blessed One until the Blessed One has explained all the multiform truths of the world-that person would die before the Buddha had explained all this."
~from the Majjhima Nikaya