did celibacy harm the gene pool in medieval Europe?

During the medieval period, most of Europe was illiterate. I imagine that if a family had a particularly intelligent son, who showed a liking to reading, he would have been encouraged to join the clergy (since they’re the ones that primarily read).

But the clergy was celibate. So did that have the effect of killing of the genes of those with a proficiency for reading (assuming there is such a gene)?

IIRC, the rules on celibacy were imperfectly enforced and poorly understood (perhaps deliberately), and until the late Middle Ages a lot of clergy still married and had kids.

And even when the Church did knuckle down and enforce it, I think there were plenty of violations of that rule, blind eyes and so on.

Think about the modern ‘celibate’ clergy. There is no evidence at all that monks and priests kept their flies buttoned. The rule may have prevented marriage, but certainly didn’t prevent bastards.

It wasn’t particularly the intelligent ones who got sent to monasteries and nunneries, it was mainly younger sons of minor gentry who were not going to inherit any land (and who, for one reason or another, did not want to be professional soldiers), and daughters whose families could not afford a decent dowry for them. That is to say, it was people who were to posh to be laborers, but, through the ill luck of having an elder brother, and the lack of the talents required for any of the rather limited range of medieval professions, had few other ways to make a living.

Yes, monks (I am not sure about nuns) would get an education in basic literacy, enough so that they could copy manuscripts (an important part of a monk’s duties). However, most monks had little education beyond that, and it does not call for any particular smarts. Of course, by the law of averages, there were a few very smart monks, who educated themselves far beyond this level. They tend to be the ones that history remembers, but they were a small minority. The average IQ of monks, and the distribution of IQ levels in the monk population, probably did not differ very much from what you would have seen in the general population.

Ordinary medieval parish priests, incidentally (who were also presumably supposed to be celibate, at least in the later middle ages), were very often not literate at all.

It was a bit different with the orders of friars, that arose in the later middle ages. The orders of friars laid great stress on education, well beyond basic literacy, for their members, and very likely did attract more scholarly minded recruits than the monasteries did. The faculties of the late medieval universities were largely composed of friars. However, on the one hand, friars were only around for two or three centuries before the renaissance kicked in (when you started getting far more literate and, even scholarly, lay people around). For a long lived species like humans, that is not long at all in evolutionary terms. On the other hand, it was an important part of a friars remit to get out and about on their own and mix with (and minister to) lay people, including women! Monks were kept locked away in their monasteries, but friars most decidedly were not. This, one may suppose, would have given them much more opportunity than monks had to break the rules about celibacy, and they would doubtless have been subjected to much more temptation, too.

Until the late Middle Ages, secular priests weren’t required to be celibate. Can’t break a rule which does not exist.

And the scriptorium work frequently was not one monk copying out one book at a time, it was a room full of monks sitting there while the reader spells out each word letter by letter and the poor bored to tears monks would write them out on preruled pages that had blanks left for the artists to make the fancy letters and decorations. I can not imagine a more boring job than to be effectively a typewriter. Not to mention that there very frequently was a heavy disparity in the level of luxuries between the poor typewriter monks and their officers - the officers tended to be the nobles, and the scriptors were peasants - and the peasants frequently got grain mush, bread, cheese and small beer with frequent fasting and good meals only on special holidays while the officers ate well.

If you wanted to “be” somebody in a monastic scriptorum, be fantastic as an artist and work as an illuminator, you got a room to work in that was warm in the winter and you didn’t have to hear someone droning on spelling out each word [frequently the scriptorums were the only deliberately toasty warm rooms in a monastary, not for the comfort of the monks but so their fingers would be able to draw and color the illustrations. The poor typewriter monks would not be kept as warm, but they would have minimal heat.]

I cannot give a cite, but when I was in HS, one teacher claimed to me (privately) that teachers were, on average, in the 4th quintile of their HS class and clergy were, on average, in the 5th quintile. Thinking about it now, I actually doubt this, but honestly there is no reason to think that the clergy were above average either.

Whether the guideline for celibacy was followed … religiously … or not is immaterial: if it was followed at all then it seems likely that those who were in the priesthood were likely to, overall, have less children. IOW they had diminished reproductive fitness. Whatever genes that were associated with becoming a priest were therefore likely to be selected against.

To take the position that there was no difference in abilities between those who became priests and the general public (or that the association was towards lesser intellect) seems untenable. Some above the mean ability to learn to read and function intellectually was likely associated to some degree with becoming and functioning as priest. Priests exerted a fair amount of power.

The fact that the younger sons of the wealthy had two choices - priests or soldiers - both of which were associated with decreased reproductive fitness (either by dint of increased rate of celibacy or by increased risk of early death) meant that whatever genes might have been associated with becoming wealthy were selected against as well.

How big of an impact this might have had would depend on how strongly those traits were gentically based, how strongly those traits impacted the becoming a priest, and the numbers involved. I’d wager little but not none.

Since we’re wagering, I’ll wager none. It’s unlikely genes had anything to do with it. And it’s unclear that priest had reduced reproductive fitness since 1) the celibacy rule was widely flouting and 2) Priests generally lead a comfortable lifestyle with access to wealthy women more likely to have better health care when they did get pregnant. A Priest with any desire to sow his oats had more more opportunity to do so than your average schmo.

Very few people became wealthy in the middle ages (or if they did, it was mostly via war, conquest, and stealing, not smarts or entrepreneurial talent). There was very little social mobility. Nearly everybody who was somewhat wealthy was so because they had inherited land (ultimately from someone who had taken it by force, usually generations ago).

The only intellectual capacity you needed to become a monk was the ability to learn to read and write, if taught. As modern educational systems prove, very nearly everybody has that. Priests did not even need that. You did not get to be a priest through your abilities, you got to be one by knowing (or by your family knowing) the right people, or perhaps by paying the right bribes.

Do you have any evidence at all that there are genes associated with being wealthy, or do you just groundlessly assume that everything comes down to genetics and that all wealth is due to genetic superiority?

Obviously there is more to reading for comprehension than just the mechanics of reading as you demonstrate - reading this:

as

:rolleyes:

I do assume that behavioral traits and abilities often have some genetic contribution. Sometimes very little, sometimes more.

The key questions are:

  1. Did those who became priests have some increased capability, on average, than the mean of the population at large?

  2. Did those who became preists have children who reached reproductive age themselves more or less often than the rest of the general population.

  3. To what degree were any differences conceded in question 1 due to a genetic factor?

I for one find the claims that there was not any, on average, difference between those who were able to become priests and those who did not to be unconvincing, claims that celibacy was flouted so universally that reproductive fitness was maintained or enhanced to be nearly absurdist, and suspect that the genetic contribution to those abilities was likely slight but nonzero.

It seems unlikely however that there is a GQ answer to this question other than that of course it is possible that such did occur and that such would have occurred if the highest in some ability were selected for celibacy each generation, that such ability had any genetic contributor at all, and that celibacy was in way at all complied with to any degree that those individuals produced fewer reproductive aged children.

Speculations that those who made a vow to be celibate actually produced more children than others around them and that no genetic factors were involved in whatever abilities were involved in becoming a priest are speculations that I see little evidence presented to support.

Do you have any evidence to support these opinions? (I would note, however, that I do not and did not maintain that the celibacy rules, once they actually became Church law, were particularly widely flouted, and that my arguments did not depend upon this. You may be right on this one, I don’t know, although I also have no particular reason to doubt other posters claims that they were widely flouted. Your other two claims, however, are baseless, and fly in the face of what evidence there actually is.)

The GQ answer has been given: the available evidence suggests that the celibacy rules are likely to have had no noticeable systematic effect on the composition of the gene pool. This is because key assumptions in the OP are false (that clergy and monks were selected for bookishness) or baseless (that there is a heritable genetic predisposition for bookishness, or something like that). Apparently you do not accept this answer because it conflicts with preconceptions that you are unwilling to give up. Your assumptions both about history and genetics, however, when not outright false are entirely conjectural.

Clergy and religious were less than 1% of the population. Even if they were all perfectly celibate, I doubt that would have had a significant effect on the population, especially since they weren’t being weeded out because of any character trait (“don’t let the redhead reproduce!”).

njtt,

I have read you claim that there was no selection factor placed on who went into the priesthood and that priest were actually not well educated. I see no support of that claim.

OTOH I can find sources that state

And this:

which conflict with that claim.

The most educated were the priestly class. The most bookish.

I am making no statements of fact because I am not in possession of them. I have no expert knowledge about the Middle Ages. You however making statements as fact is insufficient proof that your satements are true. My position remains - to the degree (if any) that the ability to learn more easily was selected for and has any genetic contribution a pattern of having those people reproduce less often would have some impact on the future gene pool. If you have some evidence to put forth that there was no such tendency for those who could learn more easily to become among the most educated and that there is zero genetic contribution to learning ability and that the priestly class reproduced as much as everyone else then put it out here and I will have my ignorance reduced. Happily. Until then I doubt your claims.

I think moriah has the most sensible response. If you could somehow do a regression analysis of all the different ways people’s genes were removed from the pool in Europe during that time frame to see their affect on the future, then it seems likely that any cause that affected less than 1% (i.e. clergy who were actually celibate) would be an extremely minor factor.

And why aren’t people asking this question for nuns, who were probably more numerous and supposedly just as celibate?

It’s hard to know if any removal of genes has precisely zero effect, but this has got to be so close that zero is a good first approximation.

Wouldn’t you need to assume that those who were celibate had no siblings who reproduced for there to be any noticeable effect? I think the percentage of people whose genes were not carried on by their siblings, and who never produced any offspring themselves due to celibacy would be rather small.

Also, in addition to as was said, the clergy not having to be celibate at all for a lot of the middle ages, and not always following the rule even when they did, clergy in minor orders never had to be celibate. You had a bunch of people running around who had gotten educated, taken minor orders, and then chose not to pursue an ecclesiastical career, but hire themselves out as scribes (clerks, from the Latin clericus, ie, clergyman) for secular individuals or organizations.

Expano, as a practical matter I’d guess most likely correct. As an intellectual exercise I wonder if even a nonrandom 1%'s effect would be so negligible if the other factors were distributed in a more random manner relative to that trait.

TriPolar, no you wouldn’t. Reducing the frequency of those (hypothetical) genes being reproduced would have an effect even if some passed on via kin. The counter to that would be if the success of those with those traits provided a reproductive advantage to kin - i.e. being closely related to the priest made you a more desirable mate, got you a more secure job, and/or gained your children some survival or reproductive advantage. Which is possible.

I remain dubious however of njtt’s statements of “fact.” Trying to find anything more authoritative to address some of those issues all I find are things like this:

DSeid, what you’re saying has levels of implication. You can make the case that a notable segment of the population, chosen for some academic ability, was singled out for the clergy. At the same time, that same quote makes the case that candidates for this distinction were found in all levels of society, including many whose parents showed no especial gifts. (This gives the lie to the noxious racism that keeps yelling about the lower classes or foreigners or dark-skinned peoples are outbreeding the upper class and so driving the world into idiocy.) You can show that educated parents tend to have educated children. It’s harder to make the case that these children are therefore smarter. Brains tend to pop up all over the place and the upper classes often inbreed until they are noticeably dim.

Therefore I think you’re overstating your case. TriPolar is quite correct that if families pass on their genes, then losing the contribution of one sibling is not a large issue. My maternal grandparents had four kids who had ten children among them. The four kids never went past high school. The ten children have far more than ten advanced degrees. In that crowd of success I’m considered the “smart” one, but I’m the only childless one. So what. Humanity will get along fine from the genes of the nine others and it will be spared the other genes that may be more negative.

And that’s the other flaw in your argument. People are a mix of positive and negative traits. What if intelligence to linked to negative traits? Perhaps it’s a good thing that those are leaving the gene pool.

That’s all in addition to the fact that probably a dozen other factors took more genes out of the pool than religious celibacy. We simply don’t know what types of genes that infant death, disease, deformity, madness, plagues, war, work accidents, random crimes, or simple infertility removed. As far as we know, however, the world is a mixture of smart, mediocre, and dumb today exactly as it has seems to have been for all recorded history. If you try to argue otherwise your first need to explain that away.

Typically monks and nuns alike had to pay a dowry to be received in a monastery/nunnery. Lay brothers didn’t have to, but were expected to provide work instead.

Being a monk/nun was a privileged position. You normally didn’t get in for free.