“We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness” – this is the first phrase of the Declaration of Independence written by Thomas Jeffferson. His hope toward “life, liberty, and the pursuit of happiness” inspired not only the American Revolution but also the French Revolution in 1789, March on Washington in 1963, and South Korea’s democratization in 1987(Office of the Historian, n.d.; Balkansky & Stanton, 2019; Raab, 2013; Kim, 1985). Protection of life, liberty, and the pursuit of happiness played its role as a beacon toward a more livable world in human history and that hope toward life, liberty, and the pursuit of happiness was often protected by biochemistry. This article introduces chemicals in human history that made that hope possible – penicillin(C16H18N2O5S) and oxytocin (C43H66N12O12S2).
(image source: Penicillin G procaine | CAS 6130-64-9 | SCBT )
The discovery of penicillin (C16H18N2O5S) literally made society more livable, as it gave people resistance to various diseases, protecting several lives. In the past, people needed a lot more luck compared to today just to stay alive. 30.4% of all deaths’ victims were children aged under 5 years old in 1900 and some of the infections became inevitably fatal (US Center for Disease Control and Prevention, 1999 & Cheng, 2023). Fortunately, the discovery of penicillin, which led to the adoption of antibiotics, made it possible for society to become a place where life, liberty, and the pursuit of happiness is protected (American Chemical Society, n.d.). Today, penicillin is used actively to protect the lives of children. The mortality of children aged 1 – 9 halved from 1990 to 2016, and according to the research, usage of antibiotics saved more children from death by 14% in regions where children’ s lives were vulnerable (Berkley, 2019, 1 & Colliver, 2024).
Another chemical that liberated “life, liberty, and the pursuit of happiness” was oxytocin(C43H66N12O12S2). Oxytocin, or a love hormone, is a brain chemical and a type of happy hormone that “helps us recognize social cues, bond with others, and cooperate in groups (Cleveland Clinic, 2025 & Xiao, 2025).” Thanks to oxytocin, humans were able to protect human rights of “life, liberty, and the pursuit of happiness”, as it played a role in strengthening social bonds and empathy in a neurobiological way (Barchi – Ferreira & Osório, 2021, 1; Xiao, 2025). For example, Germany, a nation that committed inhumane war crimes when it was hijacked by fascism, is now a country that respects people’s freedom and human dignity as they had made a society that has empathy (Federal Ministry of Justice and Consumer Protection). Not only that, when Martin Luther King, who had a same hope with Thomas Jefferson, claimed that black people also should be treated with dignity and empathy, civil acts that ratified treatment of people with respect regardless of races was passed (US Embassy & Consulate in the Republic of Korea, 2017; National Archives, 2022).
By. Hangyul Park
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