Traditionally, the origins of Roman legal science are connected to Gnaeus Flavius. Flavius is said to have published around the year 300 BC the formularies containing the words which had to be spoken in court to begin a legal action. Before the time of Flavius, these formularies are said to have been secret and known only to the priests. Their publication made it possible for non-priests to explore the meaning of these legal texts. Whether or not this story is credible, jurists were active and legal treatises were written in larger numbers before the 2nd century BC. Among the famous jurists of the republican period are Quintus Mucius Scaevola who wrote a voluminous treatise on all aspects of the law, which was very influential in later times, and Servius Sulpicius Rufus, a friend of Marcus Tullius Cicero. Thus, Rome had developed a very sophisticated legal system and a refined legal culture when the Roman republic was replaced by the monarchical system of the principate in 27 BC.