A happy life is built on pleasures such as sex and food, but also company and variety

Pleasure, despite being central to human experience and evolution, is quite hard to define. Aristotle argued that what we call pleasure is comprised of least two distinct aspects, hedonia (pleasure) and eudaimonia (human flourishing or a life well-lived). However, as Morten Kringelbach, professor at the department of psychiatry at the University of Oxford in the UK and at the Centre for Music in the Brain at Aarhus University in Denmark, points out this instalment of Aeon’s In Sight series: ‘It’s surprisingly difficult to show that somebody who is happy is also somebody who has had a lot of pleasure.’ 

Kringelbach’s research into how pleasure works in the brain seeks to find the connections between experiencing hedonistic pleasure – food, sex, drugs – and living an eudaimonic life. When all is well, he discovered, there is a system of give and take between different regions of the brain that yields experiences of pleasure that cumulatively contribute to feelings of wellbeing. However, imperfections in the mechanisms that govern pleasure in the brain leave us susceptible to conditions such as addiction, an unhealthy fixation on the pursuit of pleasure, or depression, in which both the desire for pleasure and pleasure itself are significantly diminished. A common characteristic of these and other affective disorders is that they take people away from what Kringelbach argues are the two key – often overlooked – aspects of pleasure: variety and community. Ultimately, he thinks, variation in pleasure, together with sharing that enjoyment with others, is what’s needed for a well-balanced, eudaimonic life.

Far from sluggish: the remarkable sea creature that weaponises its dinner

Nudibranchs, also commonly known as sea slugs, are a group of snail-like sea invertebrates. Despite appearing more or less defenceless, nudibranchs broadcast their whereabouts with their flamboyant, brightly coloured bodies. From an evolutionary standpoint, it might seem like a curious move, but their luminous skin actually serves as a warning to would-be predators to let them know they’d make for a dangerous meal. While some nudibranchs accumulate toxins and other defensive chemicals in their bodies, others – like the star of this film – have an even craftier method of warding off enemies. This remarkable short from the science and nature documentary series Deep Look details the clever way that some nudibranchs protect themselves by stealing defences from stinging sea animals known as hydroids. You can read more about this video at KQED Science.

‘My God! Where’s the human voice?’ A charming reflection on our pre-recorded world

From to Siri to subways to customer service calls, pre-recorded and robotic voices are becoming an increasingly inescapable part of the human experience. In this short animation from StoryCorps, the US author, historian and broadcaster Studs Terkel (1912–2008) reflects on this trend away from human interaction and toward disembodied sentence fragments. Recalling a scene from a tram ride at Atlanta airport with exceeding wit and charm, he considers the richness of the human voice, and what we lose when it’s replaced.

From canoes to cities, a frenetic celebration of the power of indigenous Canadians

In her short film Mobilize, Caroline Monnet – a Canadian filmmaker and artist of French and Algonquin origin – uses archival documentary footage to honour the restless diligence of Canada’s indigenous people. Given access to more than 700 films from the National Film Board of Canada for the project, Monnet crafts a fervent visual collage that spans the country’s rural north, where indigenous craftsmen are seen fashioning canoes, to scenes from skyscraper construction in the urban south. According to Monnet, in making the film, she sought to explore the trajectory of her own family’s history, as well as to simply bombard viewers with ‘images of indigenous people kicking ass on screen’. Heightened by a feverish score from the Inuk artist Tanya Tagaq, Monnet’s film offers a deeply original and personal perspective on the indigenous Canadian experience.

This clever and stylish 1960 film is the most fun you’ll ever have at a physics lecture

Directed by the pioneering UK documentarian Richard Leacock, Frames of Reference is a slick and surreal dive into physics fundamentals and, in particular, why everything is indeed relative. Produced for high-school physics classes, the 1960 film features the physics professors Patterson Hume and Donald Ivey of the University of Toronto explaining, through an intertwined series of lectures and clever demonstrations, how frames of reference shape perspective. Using rotating sets, camera tricks and a visual style that suggests the film noir of Alfred Hitchcock, this is perhaps the most peculiarly entertaining half-hour physics lecture you’ll ever have.