Counting Catholics

Summary

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More or Less: “Counting Catholics”

BBC Radio 4 — February 25, 2013

Host: Tim Harford

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Main Theme

This episode critically examines the oft-cited statistic that there are “1.2 billion Catholics worldwide.” Tim Harford and his guests break down how such numbers are calculated, question who actually counts as Catholic, and explore related debates about religious demographics. The show also debunks viral claims about European population trends, especially regarding Muslim demographics and so-called unstoppable shifts based on fertility rates.

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Key Discussion Points & Insights

1. Where Does the 1.2 Billion Figure Come From?

• Listener’s Question (00:54): Raises the issue of lapsed Catholics and self-identification:

  “I was born a Catholic, but now… I decided I don’t believe. Am I counted?”

• Prof. David Voas, University of Essex (01:15):

  • Catholic Counting Principle:

    “The Catholic Church counts as members of its community everyone who has been baptized…”

  • In practice, parish priests estimate parish size, partly based on Mass attendance and partly guesswork regarding sacraments and rites (baptisms, weddings, funerals).

• Difficulties with Membership Numbers (02:01):

  • Lack of systematic record-keeping, especially “counting out” when people leave or stop believing.
  • Comparison: The Mormon Church keeps people on the books unless notified or until age 110. The Catholic Church is less meticulous in removing non-participants.

• Overlap & Double-Counting (02:37):

  • People who convert to another faith may still be listed as Catholic and simultaneously counted by another religion (“especially in places like Latin America”).

2. Self-Identification as a Measure

• Alternative Approach (03:10):
  • Instead of counting baptisms, some surveys ask people how they identify.
  • Using self-identification:**

    “The best estimate is about 1.1 billion. This… will include many, many people who don’t practice, perhaps don’t even believe, but who still regard themselves as, in some sense, Catholic.” (David Voas, 03:29)

3. Debunking the “Muslim Demographics” Video

• Background: (03:38)
  • Cardinal Peter Turkson screened a viral video, “Muslim Demographics,” at the Vatican Synod, which claims rapid Islamification of Europe.
  • The video has “13.6 million views” (04:14) and makes alarming claims regarding fertility and migration.

Major Claims from the Video & Responses

• Claim: 25% of Belgians are Muslim. (05:14)
  • Truth: Recent estimate is 6% (05:39)
• Claim: 50% of newborns in the Netherlands are Muslim. (05:14)
  • Truth: No such data exists, but with an estimated 5% Muslim population, the claim is “highly unlikely.” For it to be true, “Dutch Muslims would need to be reproducing at around 14 times the rate of their non-Muslim neighbours.” (06:05)
• Claim: The Muslim population of the UK has grown 30 times in 30 years. (05:14)
  • Truth: Exaggerated by underestimating the starting number in 1981.

4. The Problems with Fertility Rates & Projections

• What Is the Total Fertility Rate (TFR)? (06:51)

  • “A hypothetical figure”: The TFR is based on current fertility of different age cohorts; assumptions for the future are inherently uncertain.

    “[Any] long term projections based on these total fertility rates are only going to be valid assuming the current rates don’t change.” (07:42)

• Claims about “irreversible decline” if rates fall below a certain point are misleading.

  • Fertility rates in Europe have actually risen in five of the six most populous countries.

• Immigrant Fertility Converges with Wider Society (08:13)

  • “Historically, the fertility rates of migrants tend to converge on those of the society they live in over time.”

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Notable Quotes & Moments

• On the Creative Counting of Catholics:

  “The Catholic Church counts as members of its community everyone who has been baptized… In practice, parish priests are asked to estimate the size of their flock.” (Prof. David Voas, 01:15)

• On Leaving the Church:

  “It would be one thing to count baptisms and another to work out when people have left, either spiritually or physically… That’s part of the problem of counting in and not having such a good system for counting out.” (Prof. David Voas, 02:01)

• On the Problems with Religious Statistics:

  “Presumably different religious denominations or different religions could be counting the same people.” (Tim Harford, 02:37) “Absolutely… especially in places like Latin America.” (Prof. Voas, 02:49)

• On Sensational Statistical Claims:

  “In the Netherlands, 50% of all newborns are Muslim.” (Viral video quoted, 05:14) “Sounds unlikely.” (Ollie Hawkins, 06:04) “Well, it is unlikely.” (Ollie Hawkins, 06:05)

• On the Limitations of Demographic Projection:

  “Population projections are so uncertain and… have been wrong so many times in the past.” (Ollie Hawkins, 07:49)

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Important Timestamps

• 00:54 – Listener’s question about being counted as Catholic if “lapsed”
• 01:09 – Prof. David Voas explains counting methods
• 03:10 – Discussion of self-identification vs. official counts
• 03:38 – Introduction of “Muslim Demographics” video and its viral impact
• 05:14 – Breakdown of video’s claims about Belgium, the Netherlands, and the UK
• 06:51 – What is the total fertility rate, and how projections work (and fail)
• 08:13 – The convergence of migrant and host society fertility rates

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Tone & Style

Informative, debunking, and gently humorous, Tim Harford’s “More or Less” aims to clarify complex numbers while calling out sloppy statistics—whether in religious membership counts or in panic-fueling demographic claims.

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Summary

This episode reveals that oft-cited statistics—like the claim that there are 1.2 billion Catholics—are fraught with methodological uncertainties and generous inclusivity, while viral fears about demographic shifts in Europe are built on selective, misleading, or non-existent data. Whether it’s counting Catholics or forecasting religious takeovers, the podcast demonstrates the necessity for skepticism and statistical literacy.

Transcript

[A]

Thank you for downloading from the BBC. For details of our complete range of podcasts and our terms of use, go to bbcworldserveys.com podcasts

[B]

hello, and welcome to More or Less on the BBC World Service. Our aim is to rid the world of its statistical sins. And I'm Tim Harford. If you're a Roman Catholic, and I dare say even if you're not, you may have noticed that Catholics are about to get a new Pope. Since Pope Benedict's announcement that he's to retire, there's been frenzied speculation about who will lead the reported 1.2 billion Catholics worldwide. But of course, as we discovered last week when checking Manchester United's claim to have 650 million followers, a reported 1.2 billion could mean anything. We've received this question from a loyal listener. Well, the listener's loyal to us, in any case.

[C]

The next leader of the world's 1.2 billion Catholics, how is the number of Catholics made up? I was born a Catholic, but now I'm not a Catholic. In the eyes of the Church, I'm lapsed. But I decided I don't believe. Am I counted?

[B]

I put this question to David Vose, who's professor of Population Studies at the University of Essex in the uk.

[D]

Well, in principle, he is, because the Catholic Church counts as members of its community everyone who has been baptized. Now, that's the principle. The practice is very different because, of course, it's hard to keep records of this huge number of people, half the Christians in the world. So in practice, parish priests are asked to estimate the size of their flock. Now, that's partly a function of how many people turn up for Mass, but they also make some sort of guesstimate of the numbers who might come along for baptisms, first communions, weddings, funerals and so on.

[B]

And then we've got this question of people leaving the Church, ceasing to believe, lapsing, or, of course, dying. At least dying on this earth plain. How does the Catholic Church account for them?

[D]

Well, that's the other difficulty, of course. It would be one thing to count baptisms and another to work out when people have left, either spiritually or physically. The Mormon Church tackles this problem in an interesting way. They basically assume that everyone stays on the books unless they hear otherwise or the person turns 110. The Catholic system is a bit more relaxed. They don't try to track people inside detail. But you're quite right, that's part of the problem of counting in and not having such a good system.

[B]

For counting out and presumably different religious denominations or different religions could be counting the same people. If someone's born a Catholic and then converts to evangelism or converts to become a Muslim, Absolutely.

[D]

I think you find that especially in places like Latin America, for example, where many people are raised Catholic but subsequently gravitate towards Evangelical Protestant or Pentecostal churches.

[B]

Do we have some independent or objective measure of the number of people in these different religions?

[D]

There is a completely different approach and that simply to ask people. And if you take self identification as the measure, then the best estimate is about 1.1 billion. This is using a very generous notion of identification and it certainly will include many, many people who don't practice, perhaps don't even believe, but who still regard themselves as, in some sense, Catholic.

[B]

David Vos now one of the frontrunners for the papacy is a Ghanaian cardinal, Peter Turksen. If chosen, he could become the first African Pope of the modern age. But this milestone isn't why we're interested in him here on More or less. We're only in it for the statistical smackdowns and Cardinal. Cardinal Turksen waded into the statistical arena last year when he screened a controversial video at the Vatican Synod. It's called Muslim Demographics and it wasn't made by the cardinal, but by persons unknown who stuck the thing on YouTube in 2009, since when it has accrued 13.6 million views.

[E]

Here's an across the entire European Union of 31 countries, the fertility is a mere 1.38. Historical research tells us these numbers are impossible to reverse. In a matter of years, Europe as we know it will cease to exist. Yet the population of Europe is not declining. Why? Immigration. Islamic immigration.

[B]

Back in 2009, we sent our intrepid reporter Ollie Hawkins to look into the statistics behind the video. Whoever posted it wouldn't reply to our messages, but here's what Ollie and I discovered when we made our own investigations.

[F]

To put it crudely, the video is claiming that because so many Muslims are migrating into Europe, and because they are having more children than non Muslim Europeans, Europe will become an Islamic society within a few decades. There are loads of statistics in the video. These are some of the more startling.

[E]

Currently in Belgium, 25% of the population are Muslim. In the Netherlands, 50% of all newborns are Muslim. In the last 30 years, the Muslim population of Great Britain rose from 82,000 to 2.5 million, a 30 fold increase.

[G]

So let's deal with those figures one at a time. Are 25% of Belgians Muslim?

[F]

No. The most recent estimate is 6%.

[G]

And what about Dutch babies? Are half of all newborns in the Netherlands Muslims?

[F]

This one is interesting because the data simply doesn't exist. Like many European countries, the Netherlands doesn't record religion in the birth statistics. However, Statistics Netherlands estimates that Muslims are 5% of the Dutch population. So if the claim is true, that would mean 5% of the population is having 50% of the babies.

[G]

That sounds unlikely.

[F]

Well, it is unlikely. We've done some sums and we think that for the claim to be true, Dutch Muslims would need to be reproducing at around 14 times the rate of their non Muslim neighbours.

[G]

The video also says that the Muslim population of the UK has grown 30 times in the last 30 years. What about that?

[F]

We think that's an exaggeration. They get the figure by estimating that the British Muslim population has grown from 82,000 to 2.5 million. But if you assume that people born in Pakistan and Bangladesh are Muslim, there were 300,000 in the 1981 census. So by underestimating the number of Muslims in Britain 30 years ago, the growth rate is made to look much more dramatic than it actually is.

[G]

So lots of the claims in the video don't really stand up to scrutiny.

[B]

But what about the overall argument?

[G]

Is Europe going to become an Islamic society in the next few decades?

[F]

Well, the video is basing its projections on something called the total fertility rate, which it claims is low for most European countries, but high for Muslim immigrants. Now, the total fertility rate is an interesting statistic because it takes the number of children women of different ages are giving birth to right now and uses those figures to estimate how many children a woman would give birth to if, and this is the important bit, if she has the current age specific fertility rates at each stage of her life.

[G]

I'm just going to try and pause and absorb that. So the total fertility rate is a hypothetical figure. It describes how many children a hypothetical, not actually real, woman would have if over the course of her life she had as many children as a typical 15 to 18 year old woman of today, and then she had as many children as a typical 18 to 25 year old of today, and so on. Is that right?

[F]

Exactly.

[G]

And any long term projections based on these total fertility rates are only going to be valid assuming the current rates don't change.

[F]

Exactly. And they do change, which is why population projections are so uncertain and why they have been wrong so many times in the past. The video suggests that once the total fertility rate of a population drops below a certain tipping point, it goes into irreversible decline. And yet in recent years, we've seen fertility rates increase from very low levels across the whole of Europe. In fact, the fertility rate is now increasing in five of the six most populous European countries.

[G]

Hang on though. Might those rising fertility rates be because of exactly what the video is talking about, which is Muslim immigrants with high birth rates?

[F]

Well, yes, they might. We don't have the data to be sure, although fertility rates in the UK have been increasing at all age ranges, especially in the over 40s, so I suspect the story is a little bit more complicated. We also need to remember that the fertility rates of immigrants can change too. Historically, the fertility rates of migrants tend to converge on those of the society they live in over time.

[B]

If only Cardinal Turksen had listened to More or less, his faux pas of showing this inaccurate video could have been avoided. We made our own video, which you can view via our BBC.co.uk More or less also the place where any candidates for the papacy can subscribe to our free podcast. We're not infallible, but we're pretty good. If you have any questions you'd like us to answer, you can contact us, as always at more or lessbc co.uk. goodbye.