Higher and more equal: a case for optimism

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Some good news for the holi­day sea­son: The hu­man pop­u­la­tion has made much progress the past few decades. We are richer, hap­pier and healthier than ever be­fore, and the world pop­u­la­tion be­came more equal. Here are data that show im­prove­ments on the most im­por­tant met­rics.


The av­er­age in­come lev­els (ad­justed for in­fla­tion) are in­creas­ing in all con­ti­nents. Global GDP per cap­ita in­creased from around $4000 in 1960, to al­most $9000 in 1990, to al­most $15.000 to­day. At the same time, the global in­come in­equal­ity is de­clin­ing, from a Gini-co­effi­cient of 67 to 57 over the last three decades. Also, the num­ber of peo­ple liv­ing in ex­treme poverty (con­sump­tion per cap­ita less than 1,90 in­ter­na­tional dol­lars per day) de­clined from 1840 mil­lion (35% of the world pop­u­la­tion) in 1990 to less than 800 mil­lion (10% of the pop­u­la­tion) to­day. That is an av­er­age rate of one per­son out of ex­treme poverty per sec­ond. In­ter­est­ingly, most peo­ple be­lief that the pro­por­tion of the world pop­u­la­tion liv­ing in ex­treme poverty has in­creased, so they have overly pes­simistic judg­ments.

Life expectancy

Life ex­pec­tancy pos­i­tively cor­re­lates with in­come and shows an in­creas­ing trend in all world re­gions over the past decades. The global av­er­age life ex­pec­tancy at birth in­creased from 52 years in 1960 over 65 years in 1990 to 72 years to­day. In­ter­est­ingly, most peo­ple tend to think that av­er­age life ex­pec­tancy is less than 60 years, so they have overly pes­simistic judg­ments. Also the healthy life ex­pec­tancy (the num­ber of healthy life years) has in­creased, and the global in­equal­ity in life ex­pec­tancy has de­creased over the past decades.

Life satis­fac­tion and happiness

The av­er­age life satis­fac­tion score (on a range from 0 to 10) and the per­centage of peo­ple who say they are happy have in­creas­ing trends and both pos­i­tively cor­re­late with in­come (GDP per cap­ita) and life ex­pec­tancy. This cor­re­la­tion is pre­sent when look­ing at differ­ent coun­tries, look­ing within coun­tries and look­ing at the evolu­tion over time. The hap­piness in­equal­ity shows a de­creas­ing trend, even in coun­tries with in­creas­ing in­come in­equal­ity. So we can ex­pect that the global in­equal­ity in life satis­fac­tion is also de­creas­ing. In­ter­est­ingly, peo­ple tend to strongly un­der­es­ti­mate the hap­piness of oth­ers, so they have overly pes­simistic judg­ments.


The to­tal fer­til­ity rate (num­ber of chil­dren born to a woman over her life­time) de­creased from 5 in 1950, to 3 in 1990, to less than 2,5 to­day. This is close to the re­place­ment level of 2,1 chil­dren. That means there is – as far as we know – only one species that man­aged to avoid over­pop­u­la­tion (or over­re­pro­duc­tion): the hu­man species. Other species have much higher fer­til­ity rates (of­ten more than 10 chil­dren per an­i­mal), which re­sults in an over­pop­u­la­tion: a lot of new­born non-hu­man an­i­mals can­not sur­vive un­til re­pro­duc­tive age. Those non-hu­man an­i­mals give birth to many chil­dren, but more than 90% of those chil­dren die soon af­ter they are born, and they ex­pe­rience a lot of prob­lems that are typ­i­cally as­so­ci­ated with over­pop­u­la­tion, such as deadly dis­eases and mass star­va­tion. Each gen­er­a­tion of a non-hu­man an­i­mal species ex­pe­riences a dras­tic col­lapse due to over­re­pro­duc­tion, be­cause more than 90% of the new­born pop­u­la­tion dies at an early age. This is an ex­treme over­re­pro­duc­tion prob­lem in na­ture. In con­trast, in the hu­man species, al­most all new­born chil­dren can have long fulfilling lives.

Africa, the area that has the high­est hu­man pop­u­la­tion growth lev­els and the high­est fer­til­ity rates (of­ten more than 4 chil­dren per woman), is still much less crowded than ar­eas where all chil­dren can have long happy lives, such as Western-Europe. The hu­man pop­u­la­tion den­sity in Africa is on av­er­age 43 peo­ple per km², com­pared to 179 peo­ple per km² in Western-Europe. Even in 2068, with an ex­pected den­sity of 130 peo­ple per km², Africa will be less densely pop­u­lated than mod­ern day Western-Europe. And by that time, the fer­til­ity rate in Africa will be dropped as well and ex­treme poverty can be erad­i­cated. So it be­comes un­likely that the hu­man species will face an over­pop­u­la­tion prob­lem of the same level as the one faced by all other wild an­i­mal species, where more than 90% of the new­born chil­dren die.


Put­ting it all to­gether, I think there is a lot of ev­i­dence to be op­ti­mistic and to ac­knowl­edge two things.

1: The world is get­ting bet­ter, so some things to im­prove the world are effec­tive and do work. There is plenty of ev­i­dence for this state­ment, as writ­ten in books such as Steven Pinker’s The Bet­ter An­gels of Our Na­ture and En­light­en­ment Now, Hans Rosling’s Fact­ful­ness, Matt Ridley’s The Ra­tional Op­ti­mist and Michael Sher­mer’s The Mo­ral Arc.

2: The world is far from good enough, so we need more effec­tive al­tru­ism to keep on im­prov­ing the world in the most effec­tive ways. Work needs to be done, es­pe­cially on re­duc­ing farm an­i­mal suffer­ing, wild an­i­mal suffer­ing and catas­trophic ex­tinc­tion risks.