What makes people grow? Love and hope

Abstract

Background: Hope and love are popular themes of literature and art in many human societies. The human physiology of love and hope is less well understood. This review presents evidence that the lack of love and/or hope delays growth disturbs development and maturation and even kills.

Main body: Love and hope intersect in promoting healthy human development. Love provides a sense of security and attachment, which are necessary for healthy physical, cognitive, and emotional development. Hope provides a sense of optimism and resilience in the face of adversity. Loving relationships can foster a sense of hope in individuals and in society by providing support systems during difficult times. Similarly, having a sense of hope can make it easier to form loving relationships by providing individuals with the confidence to connect with others. Hope and love are the fundamental basis of human biocultural reproduction, which is the human style of cooperation in the production, feeding, and care of offspring. Examples are given of the association between human growth in height with love and hope, including (1) the global "Long Depression" of 1873-1896, (2) "hospitalism" and the abuse/neglect of infants and children, (3) adoption, (4) international migration, (5) colonial conquest, and (6) social, economic, and political change in Japan between 1970 and 1990.

Conclusion: Overall, this review suggests that love and hope are both critical factors in promoting healthy human development and that they intersect in complex ways to support emotional well-being.

Keywords: Biocultural reproduction; Community effects; SEPE; Secular trend; Strategic growth.

Fig. 1

On the left, Crane, eighteenth century, by Mitsusuke (1675–1710), National Museum in Kraków. The author died in 1710, so this work is in the public domain in its country of origin and other countries and areas where the copyright term is the author’s life plus 100 years or fewer. Top right, Crane dance of the Ainu women, northern Hokkaidō, Japan. Photographer Arnold Genthe, 1869–1942, created/published 1908, Digital Id, agc a05214 https://hdl.loc.gov/loc.pnp/agc.7a05214. No known restrictions on publication. Bottom right, Cranes folded in origami paper. Artist Laitche, created: 18 December 2007. This work has been released into the public domain by its author, Laitche. This applies worldwide. In some countries, this may not be legally possible; if so, Laitche grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law

Fig. 2

Average height in centimeters of men by year of birth, 1810 to 1980. The data were derived from historical records of the heights of soldiers, conscripts, prisoners, and others. The gray rectangle denotes the time of the long depression of 1873–1896 in the USA and Western Europe. Source of image: https://ourworldindata.org/grapher/average-height-of-men-for-selected-countries?country=GBR~ITA~USA~JPN. Data source: Human Height, University of Tübingen, 2015, Link: https://uni-tuebingen.de/fakultaeten/wirtschafts-und-sozialwissenschaftliche-fakultaet/faecher/fachbereich-wirtschaftswissenschaft/wirtschaftswissenschaft/lehrstuehle/volkswirtschaftslehre/wirtschaftsgeschichte/forschung/data-hub-height.html. Retrieved: 26 March 2023

Fig. 3

Height of English factory children in 1833 compared with the National Center for Health Statistics (NCHS) references. The heights of the factory children are shown as deficits, in cm, to both the 50th percentile and the 5th percentile of the NCHS references. Original figure by B Bogin, first appeared in Bogin (2021), based on Chadwick’s data as published by Tanner [14]

Fig. 4

Hope by George Frederic Watts (1885) the Watts Gallery, Compton, Surrey. Public Domain. A blindfolded female figure sits on a globe, playing a lyre that has only a single string remaining. The background is indistinct but has one shining star (the star above Hope’s shoulder, enlarge an online image e.g., https://en.wikipedia.org/wiki/George_Frederic_Watts#/media/File:Assistants_and_George_Frederic_Watts_-_Hope_-_Google_Art_Project.jpg)

Fig. 5

Barak Obama Presidential campaign poster, 2008. Obama Poster Art by Shepard Fairey, based on a photo taken by Mannie Garcia for Associated Press. Image from https://en.wikipedia.org/wiki/File:Barack_Obama_Hope_poster.jpg. Reprinted under the Fair Use statures of United States copyright law

Fig. 6

Height distribution in z scores of Maya children and juveniles aged 5–17 years old raised in Guatemala (N = 1897) in 1998, and in two US locations in 1992 (N = 245) and in 2000 (N = 444). The width of the three distributions is almost identical despite the much shorter height of the Guatemala-raised sample

Fig. 7

The relationship between the year of birth and average adult height for Japanese born after 1870, based on government statistics. The data for students for the years 1924–1927 and for the general population for the years 1919–1926 are for height measured at ages 21–35 years. All other data are for height measured at age 20–24 years. “The average adult height of Japanese young men and women increased with time, especially in the generations of the 1940s and 1950s after World War II. However, the rate of change has slowed in generations born after the mid-1960s and has stopped in generations born after 1980” (translated from the original Japanese [87]). The upper two plots are for men and lower two plots for women. The symbols indicate: men women—high SES 20-year-old students, ● low SES 20-year-old conscripts (men), ◊ men women—low SES 20-year-old general population, men women—post-1975 students and general population. Source: Dr. Makiko Kouchi, National Institute of Advanced Industrial Science and Technology. The figure is reprinted with kind permission of the author