As Matthew said in the other thread, this is a topic worthy of discussion.
Minor seminaries have been apart of the Church’s formation for the priesthood for centuries and the Council of Trent decreed that formation for the priesthood ideally begin at age 12 in “colleges” set aside for this purpose (Session 23 Chapter XVIII).
https://history.hanover.edu/texts/trent/ct23.htmlUntil these modern times when their existence declined almost every diocese and most religious orders (except the Jesuits) either operated their own minor (high school) seminaries or sent their candidates considering the priesthood to one in another diocese. While the Jesuits did not operate minor seminaries they drew many of their vocations from their preparatory schools, where Latin and Greek were always part of the curriculum.
Also, until perhaps the early 20th century the Church has had a preference for single sex high schools, which are making something of a comeback in some urban areas. There are substantial ecclesiastical docuмents on this but I don’t have time to look them up at the moment.
I was born in 1951 and attended a parochial school. I did not go to a minor seminary but knew several who did. Back in those days the idea was that a call to the religious life came from God (i.e., NOT the idea that “I can be a priest, a doctor, a farmer, a lawyer, a plumber, I’ll pick the ‘career’ that appeals to me most”, NOR the idea that a religious vocation is somehow “planted” from scratch), God’s call was always involved. In grade school we were taught to carefully discern if the religious life might be God’s call in our lives. Most vocational recruitment occurred during middle school. Young men considering a call to the priesthood generally entered the minor seminary after 8th grade. Young men and women considering a call to the professed religious life generally became a postulant right after high school. There were always provisions for “late vocations” but what I described was the norm, and had been for many centuries.
While the least important reason perhaps, there was also a pragmatic reason for minor seminaries. It was generally necessary for one to be proficient in Latin by the time they began philosophy (the college phase of seminary, before theology), and four years of high school Latin served this purpose.
It would be interesting to know, of those currently in traditional seminaries, how many came from minor seminaries or at least traditional Catholic High Schools, and how many were home schooled or came from public high schools. I don’t know but I’m guessing the majority might be from the first two groups.
Anyways, when it comes to considering this question from the perspective of tradition, it makes sense to consider what Trent said.