Gamaliel III (Hebrew: רבן גמליאל ברבי, read as Rabban Gamaliel beRabbi, that is: son of the Rabbi, as his father was referred to as Rabbeinu HaKadosh or Rebbi). His father, Judah the Prince (Hebrew: Yehudah HaNasi; also referred to as Judah I) appointed him his successor as nasi. He lived in the 3rd century CE. Little certain is known about his activities, but it is likely that the revision of the Mishnah was completed during his era.
rabbis should be part of the (real) world: Beautiful is the study of Torah with the way of the world, for the toil of them both causes sin to be forgotten. Ultimately, all Torah study that is not accompanied with work is destined to cease and to cause sin.
moral duty towards public welfare: Those who work for the community should do so for the sake of Heaven; for then the merit of their ancestors shall aid them, and their righteousness shall endure forever.
the selfishness of politicians: Be careful of those in authority, for they will let a person near to them only for their own purposes; they act like friends when it is to their advantage, and will not stand by someone in their hour of need.
submission to the will of God: Make that His will should be your will, so that He should make your will to be as His will. Nullify your will before His will, so that He should nullify the will of others before your will.