His electoral slogan was "moderation and wisdom" and, since he became the President of Iran in August, that is precisely what he has practised.
But cleric Hassan Rouhani, the Iranian leader who recently broke decades of unremitting hostility by concluding a historic nuclear agreement with the West, continues to be an enigma.
To many, he is a symbol of a new Iran, a confident country determined to end its international isolation.
But to his critics he is, as Israeli Prime Minister Benjamin Netanyahu dismissively put it, "a wolf in sheep's clothing", someone who hoodwinks opponents by pretending to be a moderate.
The reality is probably somewhere in between; the one feature which most stands out about MrRouhani's career is his ability to navigate the shark-infested waters of Iranian politics by playing more than one role at the same time.
Born 65 years ago in the same dusty province of Semnan in northern Iran as predecessor Mahmoud Ahmadinejad, whom he replaced in office this year, Mr Rouhani's initial background offered no clues that he was destined for higher things: His family sold carpets and spices, the traditional trade of the provincial merchant class.
But it quickly became evident that he was both studious and exceptionally bright: At school, his teachers used to let him take charge of some of the classes.
His passion for religion came early, and was profound: It inspired him to change his family name from the original Fereydun to Rouhani which, roughly translated, means "spiritual man". But his love of the faith was never narrow:
He was interested in the flexibility of Islam, in what it embraces or tolerates, rather than what it rejects or bans.
A degree in religious education followed naturally. And so did Mr Rouhani's opposition to the Shah and his dynasty. By the early 1970s, he was already a marked man and had to leave the country, joining the Ayatollah Khomeini, who also opposed the Shah, in exile.