Atheism

== Demographics ==

{{Main|Demographics of atheism}}

[[File:Countries by percentage of Unaffiliated–Pew Research 2010.svg|thumb|upright=2.5|[[Irreligion by country|Nonreligious population by country]], 2010<ref>{{Cite web|url=https://www.pewforum.org/2015/04/02/religious-projection-table/|title=Religious Composition by Country, 2010-2050|date=April 2, 2015|website=Pew Research Center's Religion & Public Life Project|language=en-US|access-date=April 27, 2020|archive-date=February 15, 2019|archive-url=https://web.archive.org/web/20190215031743/http://www.pewforum.org/2015/04/02/religious-projection-table/|url-status=live}}</ref>]]

It is difficult to quantify the number of atheists in the world. Respondents to religious-belief polls may define "atheism" differently or draw different distinctions between ''atheism'', non-religious beliefs, and non-theistic religious and spiritual beliefs.<ref>{{cite web |url=http://www.adherents.com/Religions_By_Adherents.html#Nonreligious |title=Major Religions of the World Ranked by Number of Adherents, Section on accuracy of non-Religious Demographic Data |access-date=April 9, 2011 |archive-url=https://web.archive.org/web/20110422093857/http://www.adherents.com/Religions_By_Adherents.html |archive-date=April 22, 2011 |url-status=usurped}}</ref> A 2010 survey published in ''[[Encyclopædia Britannica]]'' found that the non-religious made up about 9.6% of the world's population, and atheists about 2.0%. This figure did not include those who follow atheistic religions, such as some Buddhists.<ref name="eb-2010">{{cite web |title=Religion: Year in Review 2010: Worldwide Adherents of All Religions |url=https://www.britannica.com/EBchecked/topic/1731588/Religion-Year-In-Review-2010/298437/Worldwide-Adherents-of-All-Religions |website=Encyclopædia Britannica Online |publisher=Encyclopædia Britannica Inc. |access-date=November 21, 2013 |archive-url=https://web.archive.org/web/20140702182310/https://www.britannica.com/EBchecked/topic/1731588/Religion-Year-In-Review-2010/298437/Worldwide-Adherents-of-All-Religions |archive-date=July 2, 2014 |url-status=live }}</ref> The average annual change for atheism from 2000 to 2010 was −0.17%.<ref name="eb-2010" /> Broad estimates of those who have an absence of belief in a god range from 500 million to 1.1 billion people worldwide.<ref name="CambridgeZuckerman"/><ref>{{cite book |url=https://books.google.com/books?id=rQTdki1xyK0C&pg=PA122 |title=Secularization and the World Religions |year=2010 |editor1-first=Hans |editor1-last=Joas |editor2-first=Klaus |editor2-last=Wiegandt |publisher=Liverpool University Press |isbn=978-1-84631-187-1 |ol=25285702M |page=122 (footnote 1) |access-date=April 18, 2012 |archive-url=https://web.archive.org/web/20151030194457/https://books.google.com/books?id=rQTdki1xyK0C&pg=PA122 |archive-date=October 30, 2015 |url-status=live }}</ref> Scholars have indicated that [[Desecularization|global atheism may be in decline]] as a percentage of the global population due to irreligious countries having the lowest birth rates in the world and religious countries generally having higher birth rates.<ref name=":1">[http://www.sneps.net/RD/uploads/1-Shall%20the%20Religious%20Inherit%20the%20Earth.pdf Shall the Religious Inherit the Earth?: Demography and Politics in the Twenty-First Century] {{Webarchive|url=https://web.archive.org/web/20170623024354/http://www.sneps.net/RD/uploads/1-Shall%20the%20Religious%20Inherit%20the%20Earth.pdf |date=June 23, 2017 }} by [[Eric Kaufmann]], Belfer Center, Harvard University/Birkbeck College, University of London</ref><ref name="CambridgeZuckerman">{{cite book|last=Zuckerman|first=Phil|editor1-last=Martin|editor1-first=Michael|title=The Cambridge Companion to Atheism|date=2006|doi=10.1017/CCOL0521842700.004|pages=47–66|chapter=3 - Atheism: Contemporary Numbers and Patterns|isbn=9781139001182}}</ref><ref name=":0">[https://www.huffingtonpost.co.uk/eric-kaufmann/london-a-rising-island-of-religion_b_2336699.html London: A Rising Island of Religion in a Secular Sea] {{Webarchive|url=https://web.archive.org/web/20211213124500/https://www.huffingtonpost.co.uk/eric-kaufmann/london-a-rising-island-of-religion_b_2336699.html |date=December 13, 2021 }} by [[Eric Kaufmann]], ''Huffington Post'', February 20, 2013</ref>

According to global [[WIN/GIA|Win-Gallup International]] studies, 13% of respondents were "convinced atheists" in 2012,<ref name="Gallup2012">{{cite web |url=http://www.wingia.com/en/news/win_gallup_international_ae_religiosity_and_atheism_index_ao_reveals_atheists_are_a_small_minority_in_the_early_years_of_21st_century/14/ |title=WIN-Gallup International "Religiosity and Atheism Index" reveals atheists are a small minority in the early years of 21st century |date=August 6, 2012 |access-date=August 28, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120825005955/http://www.wingia.com/en/news/win_gallup_international_ae_religiosity_and_atheism_index_ao_reveals_atheists_are_a_small_minority_in_the_early_years_of_21st_century/14 |archive-date=August 25, 2012 }}</ref> 11% were "convinced atheists" in 2015,<ref name="wingia2">{{cite news |author=<!--none specified--> |url=https://www.npr.org/blogs/thetwo-way/2015/04/13/399338834/new-survey-shows-the-worlds-most-and-least-religious-places |title=New Survey Shows the World's Most and Least Religious Places |newspaper=[[NPR]] |date=April 13, 2015 |access-date=April 29, 2015 |archive-url=https://web.archive.org/web/20150506110630/http://www.npr.org/blogs/thetwo-way/2015/04/13/399338834/new-survey-shows-the-worlds-most-and-least-religious-places |archive-date=May 6, 2015 |url-status=live }}</ref> and in 2017, 9% were "convinced atheists".<ref name="WINGIA 2017">{{Cite web |url=http://www.wingia.com/web/files/news/370/file/370.pdf|archive-url=https://web.archive.org/web/20171114113506/http://www.wingia.com/web/files/news/370/file/370.pdf|url-status=dead|archive-date=November 14, 2017 |title=Religion prevails in the world |date=November 14, 2017|access-date=February 27, 2018}}</ref> {{as of|2012}}, the top 10 surveyed countries with people who viewed themselves as "convinced atheists" were [[China]] (47%), [[Japan]] (31%), the [[Czech Republic]] (30%), [[France]] (29%), [[South Korea]] (15%), [[Germany]] (15%), [[Netherlands]] (14%), [[Austria]] (10%), [[Iceland]] (10%), [[Australia]] (10%), and [[Republic of Ireland|Ireland]] (10%).<ref>{{cite web |title=Global Index of Religion and Atheism |url=http://redcresearch.ie/wp-content/uploads/2012/08/RED-C-press-release-Religion-and-Atheism-25-7-12.pdf |publisher=[[Gallup (company)|Gallup]] – [[Red C]] |ref=REDC |url-status=dead |archive-url=https://web.archive.org/web/20121016062403/http://redcresearch.ie/wp-content/uploads/2012/08/RED-C-press-release-Religion-and-Atheism-25-7-12.pdf |archive-date=October 16, 2012}}</ref> A 2012 study by the NORC found that East Germany had the highest percentage of atheists while Czech Republic had the second highest amount.<ref>{{cite web |last1=Smith |first1=Tom W. |title=Beliefs about God across Time and Countries |url=https://www.norc.org/PDFs/Beliefs_about_God_Report.pdf |access-date=February 26, 2021 |location=NORC, University of Chicago |page=7 |language=en |date=April 18, 2012 |archive-date=May 22, 2019 |archive-url=https://web.archive.org/web/20190522083304/http://www.norc.org/PDFs/Beliefs_about_God_Report.pdf |url-status=live }}</ref>

The number of atheists per country is strongly correlated with the level of security for both the individual and society, with some exceptions.<ref name="Martin2007">{{cite book |last=Zuckerman |first=Phil |url=https://books.google.com/books?id=tAeFipOVx4MC&pg=PA56 |title=The Cambridge Companion to Atheism |publisher=Cambridge University Press |year=2007 |isbn=978-0-521-60367-6 |editor=Martin, Michael T |location=Cambridge |pages=55, 57 |ol=22379448M |access-date=April 9, 2011 |archive-url=https://web.archive.org/web/20151031223718/https://books.google.com/books?id=tAeFipOVx4MC&pg=PA56 |archive-date=October 31, 2015 |url-status=live}}</ref>

=== Europe ===
[[File:Europe No Belief enhanced 2010.png|thumb|Percentage of people in various European countries who said: "I don't believe there is any sort of spirit, God or life force." (2010)<ref name=EB2010>{{cite web |url=http://ec.europa.eu/public_opinion/archives/ebs/ebs_341_en.pdf |title=Special Eurobarometer: Biotechnology |page=381 |date=October 2010 |url-status=dead |archive-url=https://web.archive.org/web/20101215001129/http://ec.europa.eu/public_opinion/archives/ebs/ebs_341_en.pdf |archive-date=December 15, 2010}}</ref>]]

According to the 2010 Eurobarometer Poll, the percentage of those polled who agreed with the statement "you don't believe there is any sort of spirit, God or life force" varied from a high percentage in France (40%), Czech Republic (37%), Sweden (34%), Netherlands (30%), and Estonia (29%); medium-high percentage in Germany (27%), Belgium (27%), UK (25%); to very low in Poland (5%), Greece (4%), Cyprus (3%), Malta (2%), and Romania (1%), with the European Union as a whole at 20%.<ref name="EU">{{cite book |title=Social values, Science and Technology |publisher=Directorate General Research, European Union |year=2010 |pages=207 |url=http://ec.europa.eu/public_opinion/archives/ebs/ebs_341_en.pdf |access-date=April 9, 2011 |archive-url=https://web.archive.org/web/20110430163128/http://ec.europa.eu/public_opinion/archives/ebs/ebs_225_report_en.pdf |archive-date=April 30, 2011 |url-status=dead}}</ref> In a 2012 Eurobarometer poll on discrimination in the European Union, 16% of those polled considered themselves non-believers/agnostics, and 7% considered themselves atheists.<ref>{{citation |title=Discrimination in the EU in 2012 |work=[[Eurobarometer|Special Eurobarometer]] |year=2012 |series=383 |page=233 |url=http://ec.europa.eu/public_opinion/archives/ebs/ebs_393_en.pdf |access-date=August 14, 2013 |publisher=[[European Commission]] |location=[[European Union]] |url-status=dead |archive-url=https://web.archive.org/web/20121202023700/http://ec.europa.eu/public_opinion/archives/ebs/ebs_393_en.pdf |archive-date=December 2, 2012}} The question asked was "Do you consider yourself to be&nbsp;...?", with a card showing: Catholic, Orthodox, Protestant, Other Christian, Jewish, Muslim, Sikh, Buddhist, Hindu, Atheist, and non-believer/agnostic. Space was given for Other (Spontaneous) and DK. Jewish, Sikh, Buddhist, Hindu did not reach the 1% threshold.</ref>

According to a [[Pew Research Center]] survey in 2012, about 18% of Europeans are [[Irreligion|religiously unaffiliated]], including agnostics and atheists.<ref name="Religiously Unaffiliated">{{cite web |url=http://www.pewforum.org/global-religious-landscape-unaffiliated.aspx |title=Religiously Unaffiliated |date=December 18, 2012 |website=Pew Research Center's Religion & Public Life Project |access-date=November 7, 2014 |archive-url=https://web.archive.org/web/20130730043126/http://www.pewforum.org/global-religious-landscape-unaffiliated.aspx |archive-date=July 30, 2013 |url-status=live }}</ref> According to the same survey, the religiously unaffiliated are the majority of the population only in two European countries: Czech Republic (75%) and Estonia (60%).<ref name="Religiously Unaffiliated" />

=== Asia ===
There are three countries and [[Special administrative regions of China|one special administrative region of China]] or regions where the religiously unaffiliated make up a majority of the population: [[Irreligion in North Korea|North Korea]] (71%), [[Religion in Japan#Opposition to organised religion|Japan]] (57%), Hong Kong (56%), and China (52%).<ref name="Religiously Unaffiliated" />

=== Australasia ===

According to the [[2021 Australian census|2021 Australian Census]], 38% of Australians have "no religion", a category that includes atheists.<ref>{{Cite web |title=2021 Australia, Census All persons QuickStats  |url=https://www.abs.gov.au/census/find-census-data/quickstats/2021/AUS |access-date=2023-04-09 |website=Australian Bureau of Statistics |archive-date=March 29, 2023 |archive-url=https://web.archive.org/web/20230329231159/https://www.abs.gov.au/census/find-census-data/quickstats/2021/AUS |url-status=live }}</ref>

In a 2018 census, 48.2% of [[New Zealanders]] reported having no religion, up from 30% in 1991.<ref>{{Cite web |url=https://www.stats.govt.nz/tools/2018-census-place-summaries/new-zealand#religion |title=Place Summaries {{!}} New Zealand |website=Stats NZ |access-date=Nov 28, 2023 |archive-url=https://web.archive.org/web/20231127073855/https://www.stats.govt.nz/tools/2018-census-place-summaries/new-zealand#religion |archive-date=Nov 27, 2023 |url-status=live }}</ref>

=== United States ===

[[File:Atheismsymbol endorsed by AAI.svg|thumb|right|upright=0.6|Symbol of atheism endorsed by the [[Atheist Alliance International]]<ref>{{Cite web|url=https://atheistzone.com/|title=Atheist Zone|access-date=May 23, 2023|archive-date=May 18, 2023|archive-url=https://web.archive.org/web/20230518005431/https://atheistzone.com/|url-status=live}}</ref><ref>{{cite web |url=http://www.atheistalliance.org/secular/articles/v12n3_conventionpt5.pdf |title=PDF of the Secular Nation article "A Conventioneer's Delight! Pt 5 of 5" |archive-url=https://web.archive.org/web/20081121031350/http://atheistalliance.org//secular/articles/v12n3_conventionpt5.pdf |archive-date=2008-11-21}}</ref>]]
According to the [[World Values Survey]], 4.4% of Americans self-identified as atheists in 2014.<ref name="WVS">{{cite web |title=WVS Database |url=http://www.worldvaluessurvey.org/WVSOnline.jsp |website=World Values Survey |publisher=Institute for Comparative Survey Research |date=March 2015 |access-date=January 7, 2016 |archive-url=https://web.archive.org/web/20160105141038/http://www.worldvaluessurvey.org/WVSOnline.jsp |archive-date=January 5, 2016 |url-status=live }}</ref> However, the same survey showed that 11.1% of all respondents stated "no" when asked if they believed in God.<ref name="WVS" /> According to a 2014 report by the Pew Research Center, 3.1% of the US adult population identify as atheist, up from 1.6% in 2007; and within the religiously unaffiliated (or "no religion") demographic, atheists made up 13.6%.<ref>[http://www.pewforum.org/2015/05/12/americas-changing-religious-landscape/ America's Changing Religious Landscape] {{Webarchive|url=https://web.archive.org/web/20190410223438/https://www.pewforum.org/2015/05/12/americas-changing-religious-landscape/ |date=April 10, 2019 }}, Pew Research Center, May 12, 2015.</ref> According to the 2015 General Sociological Survey the number of atheists and agnostics in the US has remained relatively flat in the past 23 years since in 1991 only 2% identified as atheist and 4% identified as agnostic and in 2014 only 3% identified as atheists and 5% identified as agnostics.<ref name="GSS 2014">{{cite web |last1=Hout |first1=Michael |last2=Smith |first2=Tom W. |title=Fewer Americans Affiliate with Organized Religions, Belief and Practice Unchanged: Key Findings from the 2014 General Social Survey |url=http://www.norc.org/PDFs/GSS%20Reports/GSS_Religion_2014.pdf |website=General Social Survey |publisher=NORC |date=March 2015 |access-date=July 19, 2015 |archive-url=https://web.archive.org/web/20150713122450/http://www.norc.org/PDFs/GSS%20Reports/GSS_Religion_2014.pdf |archive-date=July 13, 2015 |url-status=live }}</ref>

According to the American Family Survey, 34% were found to be religiously unaffiliated in 2017 (23% 'nothing in particular', 6% agnostic, 5% atheist).<ref>{{Cite web |url=https://www.christiantoday.com/article/nones-are-now-the-biggest-religious-group-in-the-us-with-families-torn-on-priorities/118935.htm |title='Nones' are now the biggest religious group in the US – with families torn on priorities |website=www.christiantoday.com |date=November 17, 2017 |language=en |access-date=December 6, 2017 |archive-url=https://web.archive.org/web/20171206140155/https://www.christiantoday.com/article/nones-are-now-the-biggest-religious-group-in-the-us-with-families-torn-on-priorities/118935.htm |archive-date=December 6, 2017 |url-status=live }}</ref><ref>{{Cite web |url=https://www.deseretnews.com/american-family-survey/2017 |title=DN American Family Survey 2017 |website=DeseretNews.com |language=en |access-date=December 6, 2017 |archive-url=https://web.archive.org/web/20171206144335/https://www.deseretnews.com/american-family-survey/2017 |archive-date=December 6, 2017 |url-status=live }}</ref> According to the Pew Research Center, in 2014, 22.8% of the American population does not identify with a religion, including atheists (3.1%) and agnostics (4%).<ref>{{cite web |url=http://www.pewforum.org/2015/05/12/americas-changing-religious-landscape/ |title=America's Changing Religious Landscape |publisher=[[Pew Research Center]]: Religion & Public Life |date=May 12, 2015 |access-date=May 12, 2015 |archive-url=https://web.archive.org/web/20190410223438/https://www.pewforum.org/2015/05/12/americas-changing-religious-landscape/ |archive-date=April 10, 2019 |url-status=live }}</ref> According to a PRRI survey, 24% of the population is unaffiliated. Atheists and agnostics combined make up about a quarter of this unaffiliated demographic.<ref>{{Cite news |url=https://www.prri.org/research/american-religious-landscape-christian-religiously-unaffiliated/ |title=America's Changing Religious Identity |work=PRRI |access-date=December 16, 2017 |language=en-US |archive-url=https://web.archive.org/web/20180131052457/https://www.prri.org/research/american-religious-landscape-christian-religiously-unaffiliated/ |archive-date=January 31, 2018 |url-status=live }}</ref> According to a 2023 [[Pew Research Center]] study, 28% of Americans are religiously unaffiliated.<ref>{{Cite web |last=Alper |first=Gregory A. Smith, Patricia Tevington, Justin Nortey, Michael Rotolo, Asta Kallo and Becka A. |date=2024-01-24 |title=Religious ‘Nones’ in America: Who They Are and What They Believe |url=https://www.pewresearch.org/religion/2024/01/24/religious-nones-in-america-who-they-are-and-what-they-believe/ |access-date=2024-03-10 |website=Pew Research Center's Religion & Public Life Project |language=en-US}}</ref>

=== Arab world ===

In recent years, the profile of atheism has risen substantially in the [[Arab world]].<ref name="auto">{{cite web |url=https://newhumanist.org.uk/articles/4898/the-rise-of-arab-atheism |title=The rise of Arab atheism |date=June 29, 2015 |access-date=February 8, 2016 |archive-url=https://web.archive.org/web/20160206085946/https://newhumanist.org.uk/articles/4898/the-rise-of-arab-atheism |archive-date=February 6, 2016 |url-status=live }}</ref> In major cities across the region, such as [[Cairo]], atheists have been organizing in cafés and social media, despite regular crackdowns from authoritarian governments.<ref name="auto" /> A 2012 poll by Gallup International revealed that 5% of Saudis considered themselves to be "convinced atheists".<ref name="auto" /> However, very few young people in the Arab world have atheists in their circle of friends or acquaintances. According to one study, less than 1% did in Morocco, Egypt, Saudi Arabia, or Jordan; only 3% to 7% in the United Arab Emirates, Bahrain, Kuwait, and Palestine.<ref name="Tabah2016">[http://mmgsurvey.tabahfoundation.org/downloads/mmgsurvey_full_En_web.pdf Muslim Millennial Attitudes on Religion and Religious Leadership, Arab World] {{Webarchive|url=https://web.archive.org/web/20160208013343/http://mmgsurvey.tabahfoundation.org/downloads/mmgsurvey_full_En_web.pdf |date=February 8, 2016 }}, Tabah Foundation, Abu Dhabi, 2016</ref> When asked whether they have "seen or heard traces of atheism in [their] locality, community, and society" only about 3% to 8% responded yes in all the countries surveyed. The only exception was the UAE, with a percentage of 51%.<ref name="Tabah2016" />

=== Attitudes toward atheism ===

{{See also|Discrimination against atheists}}

Statistically, atheists are held in poor regard across the globe. Non-atheists seem to implicitly view atheists as prone to exhibit immoral behaviors.<ref>{{cite journal |last1=Gervais |first1=Will M. |last2=Xygalatas |first2=Dimitris |last3=McKay |first3=Ryan T. |last4=van Elk |first4=Michiel |last5=Buchtel |first5=Emma E. |last6=Aveyard |first6=Mark |last7=Schiavone |first7=Sarah R. |last8=Dar-Nimrod |first8=Ilan |last9=Svedholm-Häkkinen |first9=Annika M. |last10=Riekki |first10=Tapani |last11=Klocová |first11=Eva Kundtová |last12=Ramsay |first12=Jonathan E. |last13=Bulbulia |first13=Joseph |title=Global evidence of extreme intuitive moral prejudice against atheists |journal=Nature Human Behaviour |date=August 7, 2017 |volume=1 |issue=8 |page=0151 |doi=10.1038/s41562-017-0151 |url=http://psyarxiv.com/csnp2/ |access-date=September 11, 2018 |archive-url=https://web.archive.org/web/20180118224040/https://psyarxiv.com/csnp2/ |archive-date=January 18, 2018 |url-status=live |hdl=10138/246517 |s2cid=45851307 |hdl-access=free }}</ref> In addition, according to a 2016 [[Pew Research Center]] publication, 15% of French people, 45% of Americans, and 99% of Indonesians explicitly believe that a person must believe in God to be moral. Pew furthermore noted that, in a U.S. poll, atheists and Muslims tied for the lowest rating among the major religious demographics on a "[[feeling thermometer]]".<ref>{{cite web |title=10 facts about atheists |url=http://www.pewresearch.org/fact-tank/2016/06/01/10-facts-about-atheists/ |website=Pew Research Center |access-date=January 23, 2018 |date=June 1, 2016 |archive-url=https://web.archive.org/web/20180121114119/http://www.pewresearch.org/fact-tank/2016/06/01/10-facts-about-atheists/ |archive-date=January 21, 2018 |url-status=live }}</ref> Also, a study of religious college students found that they were more likely to perceive and interact with atheists negatively after considering their mortality, suggesting that these attitudes may be the result of [[Death anxiety#Religiosity|death anxiety]].<ref>{{Cite journal|last1=Cook|first1=Corey L.|last2=Cohen|first2=Florette|last3=Solomon|first3=Sheldon|date=September 1, 2015|title=What If They're Right About the Afterlife? Evidence of the Role of Existential Threat on Anti-Atheist Prejudice|url=https://doi.org/10.1177/1948550615584200|journal=Social Psychological and Personality Science|language=en|volume=6|issue=7|pages=840–846|doi=10.1177/1948550615584200|s2cid=145425706|issn=1948-5506}}</ref>

=== Wealth, education, and reasoning style ===

{{Further|Religiosity and education}}

[[File:2012-02-14_UAAR_Darwin_Day_Pievani_01.jpg|thumb|Darwin Day 2012 in Rome organised by Italian atheists and agnostics.]]
Various studies have reported positive correlations between levels of education, wealth and [[Intelligence quotient|IQ]] with atheism.<ref name="VyseSI">{{cite journal |last1=Vyse |first1=Stuart |title=Are atheists sadder but wiser? |journal=Skeptical Inquirer |date=April 2020 |volume=44 |issue=2 |pages=31–33}}</ref><ref name="GeggelLiveScience">{{cite web |last1=Geggel |first1=Laura |title=Why are atheists generally smarter than religious people |url=https://www.livescience.com/59361-why-are-atheists-generally-more-intelligent.html |website=LiveScience |date=June 5, 2017 |publisher=Future US Inc. |access-date=March 24, 2020 |archive-date=March 24, 2020 |archive-url=https://web.archive.org/web/20200324203444/https://www.livescience.com/59361-why-are-atheists-generally-more-intelligent.html |url-status=live }}</ref><ref name="intmag">{{Cite journal |last1=Lynn |first1=Richard |author-link=Richard Lynn |last2=Harvey |first2=John |last3=Nyborg |first3=Helmuth |title=Average intelligence predicts atheism rates across 137 nations |journal=[[Intelligence (journal)|Intelligence]] |year=2009 |volume=37 |pages=11–15 |doi=10.1016/j.intell.2008.03.004}}</ref><ref name="Zuckerman" /> In a 2008 study, researchers found intelligence to be negatively related to religious belief in Europe and the United States. In a sample of 137 countries, the correlation between national IQ and disbelief in God was found to be 0.60.<ref name="intmag"/> According to evolutionary psychologist [[Nigel Barber]], atheism blossoms in places where most people feel economically secure, particularly in the [[Social democracy|social democracies]] of Europe, as there is less uncertainty about the future with extensive social safety nets and better health care resulting in a greater quality of life and higher life expectancy. By contrast, in underdeveloped countries, there are far fewer atheists.<ref>Nigel Barber (May 18, 2010). [https://www.psychologytoday.com/us/blog/the-human-beast/201005/why-atheism-will-replace-religion Why Atheism Will Replace Religion] . ''[[Psychology Today]]''. Retrieved March 17, 2021.</ref>

The relationship between atheism and IQ, while statistically significant, is not a large one, and the reason for the relationship is not well understood.<ref name="VyseSI" /> One hypothesis is that the negative relationship between IQ and religiosity is mediated by individual differences in nonconformity; in many countries, religious belief is a conformist choice, and there is evidence that more intelligent people are less likely to conform.<ref>{{cite journal |last1=Rhodes |first1=Nancy |last2=Wood |first2=Wendy |title=Self-esteem and intelligence affect influenceability |journal=Psychological Bulletin |date=1992 |volume=111 |issue=1 |pages=156–171 |doi=10.1037/0033-2909.111.1.156}}</ref> Another theory is that people of higher IQ are more likely to engage in analytical reasoning, and that disbelief in religion results from the application of higher-level analytical reasoning to the assessment of religious claims.<ref name="VyseSI" />

In a 2017 study, it was shown that compared to religious individuals, atheists have higher reasoning capacities and this difference seemed to be unrelated to sociodemographic factors such as age, education and country of origin.<ref>{{cite journal |last1=Daws |first1=Richard |last2=Hampshire |first2=Adam |title=The Negative Relationship between Reasoning and Religiosity Is Underpinned by a Bias for Intuitive Responses Specifically When Intuition and Logic Are in Conflict |journal=Frontiers in Psychology |date=December 19, 2017 |volume=8 |issue=2191 |page=2191 |doi=10.3389/fpsyg.2017.02191 |pmid=29312057 |pmc=5742220 |doi-access=free }}</ref> In a 2015 study, researchers found that atheists score higher on cognitive reflection tests than theists, the authors wrote that "The fact that atheists score higher agrees with the literature showing that belief is an automatic manifestation of the mind and its default mode. Disbelieving seems to require deliberative cognitive ability."<ref>{{cite journal |last1=Da Silva |first1=Sergio |last2=Matsushita |first2=Raul |last3=Seifert |first3=Guilherme |last4=De Carvalho |first4=Mateus |title=Atheists score higher on cognitive reflection tests |journal=MPRA Paper |issue=68451 |url=https://mpra.ub.uni-muenchen.de/68451/2/MPRA_paper_68451.pdf |access-date=July 20, 2020 |archive-date=March 21, 2022 |archive-url=https://web.archive.org/web/20220321211303/https://mpra.ub.uni-muenchen.de/68451/2/MPRA_paper_68451.pdf |url-status=live }}</ref> A 2016 study, in which 4 new studies were reported and a meta-analysis of all previous research on the topic was performed, found that self-identified atheists scored 18.7% higher than theists on the cognitive reflection test and there is a negative correlation between religiosity and analytical thinking. The authors note that recently "it has been argued that analytic thinkers are not actually less religious; rather, the putative association may be a result of religiosity typically being measured after analytic thinking (an order effect)," however, they state "Our results indicate that the association between analytical thinking and religious disbelief is not caused by a simple order effect. There is good evidence that atheists and agnostics are more reflective than religious believers."<ref>{{cite journal |last1=Pennycook |first1=Gordon |author-link=Gordon Pennycook |last2=Ross |first2=Robert |last3=Koehler |first3=Derek |last4=Fugelsang |first4=Jonathan |date=April 2016 |title=Atheists and Agnostics Are More Reflective than Religious Believers: Four Empirical Studies and a Meta-Analysis |url= |journal=PLOS ONE |volume=11 |issue=4 |pages=e0153039 |bibcode=2016PLoSO..1153039P |doi=10.1371/journal.pone.0153039 |pmc=4824409 |pmid=27054566 |doi-access=free}}</ref> This "analytic atheist" effect has also been found among academic philosophers, even when controlling for about a dozen potential confounds such as education.<ref>{{cite journal |last1=Byrd |first1=Nick |title=Great Minds do not Think Alike: Philosophers' Views Predicted by Reflection, Education, Personality, and Other Demographic Differences |journal=Review of Philosophy and Psychology |date=2022 |volume=14 |issue=2 |pages=647–684 |doi=10.1007/s13164-022-00628-y |s2cid=247911367 |url=https://doi.org/10.1007/s13164-022-00628-y}}</ref>

However, some studies do not detect this correlation between atheism and analytic thinking in all of the countries that they study,<ref>{{cite journal |last1=Gervais |first1=Will M. |last2=van Elk |first2=Michiel |last3=Xygalatas |first3=Dimitris |last4=McKay |first4=Ryan |last5=Aveyard |first5=Mark |last6=Buchtel |first6=Emma E. |last7=Dar-Nimrod |first7=Ilan |last8=Klocová |first8=Eva Kundtová |last9=Ramsay |first9=Jonathan E. |last10=Riekki |first10=Tapani |last11=Svedholm-Häkkinen |first11=Annika M. |last12=Bulbulia |first12=Joseph |title=Analytic atheism: A cross-culturally weak and fickle phenomenon? |journal=Judgment and Decision-making |date=2018 |volume=13 |issue=3 |pages=268–274 |doi=10.1017/S1930297500007701 |url=http://journal.sjdm.org/18/18228/jdm18228.pdf |access-date=April 6, 2022 |archive-date=February 21, 2022 |archive-url=https://web.archive.org/web/20220221113759/http://journal.sjdm.org/18/18228/jdm18228.pdf |url-status=live }}</ref> suggesting that the relationship between analytic thinking and atheism may depend on culture.<ref>{{cite journal |last1=Gervais |first1=Will M. |last2=Najle |first2=Maxine B. |last3=Caluori |first3=Nava |title=The Origins of Religious Disbelief: A Dual Inheritance Approach |journal=Social Psychological and Personality Science |date=2021 |volume=12 |issue=7 |pages=1369–1379 |doi=10.1177/1948550621994001 |s2cid=233804304 |url=https://doi.org/10.1177/1948550621994001}}</ref> There is also evidence that gender may be involved in the so-called analytic atheist effect: because men have been found more likely to endorse atheism,<ref>{{cite journal |last1=Schnell |first1=Tatjana |last2=de Boer |first2=Elpine |last3=Alma |first3=Hans |title=Worlds apart? Atheist, agnostic, and humanist worldviews in three European countries |journal=Psychology of Religion and Spirituality |date=2021 |volume=15 |pages=83–93 |doi=10.1037/rel0000446 |hdl=1887/3307612 |s2cid=242996508 |url=https://doi.org/10.1037/rel0000446|hdl-access=free }}</ref> and men often perform slightly better on tests of analytic thinking<ref>{{cite journal |last1=Maloney |first1=Erin A. |last2=Retanal |first2=Fraulein |title=Higher math anxious people have a lower need for cognition and are less reflective in their thinking |journal=Acta Psychologica |date=2021 |volume=202 |page=102939 |doi=10.1016/j.actpsy.2019.102939 |pmid=31805479 |s2cid=208768799 |url=https://doi.org/10.1016/j.actpsy.2019.102939}}</ref> when not controlling for variables such as math anxiety,<ref>{{cite journal |last1=Primi |first1=Caterina |last2=Donati |first2=Maria Anna |last3=Chiesi |first3=Francesca |last4=Morsanyi |first4=Kinga |title=Are there gender differences in cognitive reflection? Invariance and differences related to mathematics |journal=Thinking & Reasoning |date=2018 |volume=24 |issue=2 |pages=258–279 |doi=10.1080/13546783.2017.1387606 |s2cid=55892851 |url=https://doi.org/10.1080/13546783.2017.1387606}}</ref> the correlation between atheism and analytic reasoning may be partly explained by whatever explains observed gender differences in analytic thinking.