While many Israelis will grumble against an injustice with the words, “lo fair” (“It’s not fair”), there is an authentic Hebrew word for fair or appropriate: hogen.
Maimondies writes in his “Laws of Torah Study” (4:1): “We teach Torah only to a student who is hagun and pleasant in his deeds.” Upright behaviour is a prerequisite for Torah scholarship.
When discussing the meaning of the prohibition of placing a stumbling block before a blind man (Leviticus 19:14), the Safra states, “Do not give someone advice that is not hogenet to him” — appropriate to his situation.
Higayon means logic. Rabbi Abraham ibn Ezra, the biblical commentator who also wrote on grammar and mathematics, declares: “An educated person must know the wisdom of higayon for the sake of his Torah study.” He was referring to the Greek system of logic that was popular in Muslim Spain and could be a useful hermeneutic tool.
The Talmujd (Ta’anit 7a) mentions three people who spoke shelo kahogen, inappropriately. The worst example was Jephthah (Judges 11:31) who promised to sacrifice to God the first thing that came forth from his house — and his daughter was to pay the price.