In the ancient Jewish world, a new month was determined by eye-witnesses. People who saw the glimmer of a crescent would come to the Sanhedrin and testify. If their testimony was accepted, the head of the Sanhedrin would declare the start of a new month. If someone disagreed with his determination, he would be challenging the authority of the head of the Sanhedrin. And that is what once happened, according to a famous mishnah in Tractate Rosh Hashanah. We will read this mishnah and try to figure out what it says about human truth vs. cosmic truth. Text handouts in Hebrew and English.