One who is half-slave and half-free works one day for his master and one day for himself; [these are] the words of Beis Hillel. Beis Shammai said to them: You have provided a solution for his master, but for [him] himself you have not provided a solution: He cannot marry a slave, because he is half-free; [and he cannot marry] a free woman, because he is half-slave. Shall he remain idle? But was not the world created only for propagation, as it says (Isaiah 45:18): He created it not a waste; he formed it to be inhabited. Rather, for the sake of the general good, his master is compelled to free him, and he writes a bond for half his value. [Subsequently] Beis Hillel retracted, and taught in accordance with the words of Beis Shammai.