Aleks Krotoski asks if how we use technology has affected our attitudes to ephemerality and the transience of things. Producer: Peter McManus

There are many ways in which the taint of prejudice, outdated ways of thinking and plain old human error can enter our artificial intelligence systems. The weakest link is always where the sticky handprints of humans are most visible. To train AIs, systems need two things: computer vision, to precisely identify images, and machine learning algorithms. But they also need a person to label images over and over and over again, so when the AI perceives that image they learn what it is. In this episode Aleks Krotoski takes a look at affect recognition and explores how it became part of a multi-billion dollar AI industry. It all comes back to a system called FACS or Facial Action Coding System, which was devised by a psychologist called Dr Paul Ekman. FACS is a framework which categorises facial expressions and was widely adopted by artificial labs in the nineties for use in computer vision. But, the science behind FACS has been widely disputed in the science community for two centuries. From a Parisian asylum, via the tropical rainforests of Papua New Guinea, Aleks Krotoski traces the history of this controversial science and tells the story of how it ended up in our AIs. Producer: Caitlin Smith

We've all had experiences of our attention wandering, usually at those moments when we most need to concentrate. But, in our productivity-driven society, are we placing too much emphasis on paying attention and failing to recognise the benefits of more unstructured thought processes? After all, focus comes at a cost. With numerous demands on our attention, it's all too easy to experience burnout. Unfocus can recharge our batteries and allow us to be creative by making connections and connecting with other people. In this episode, Aleks Krotoski explores some of the different modes of attention we can switch between and asks whether, perhaps, we should be awarding our unfocus equal status to our focus. Producer: Lynsey Moyes

If you want to send a message without any chance of it being intercepted then end-to-end encryption services are the way to do it. Governments and intelligence agencies can’t even intercept these messages, without compromising the phone they’re sent or received on, because the tech companies themselves don’t even have access. In the pursuit of protecting people’s privacy, in the wrong hands these messaging apps can be dangerous. Aleks discovers how the Taliban used WhatsApp to help them sweep through Afghanistan and take Kabul, without a bullet being fired. Unless you turn off the internet it's impossible with technology like WhatsApp, Telegram and Signal to let the ‘good’ guys use it while restricting the ‘bad’ guys. Aleks hears why turning off the internet is not the answer because it often favours those who are trying to oppress rather than the people who need help. Aleks learns that while the Taliban were using WhatsApp to organise and disarm those who may have tried to resist their takeover of Afghanistan, many Afghans who were desperately trying to escape Kabul relied on WhatsApp to connect and keep in touch with military officers and diplomats in order to get to and through the right gate and onto flights to safety. For some, when their phone battery ran out so did their hopes of escape. "WhatsApp has provided a lifeline to millions of people around the world and we're grateful to have played a small role in helping people in Afghanistan. Of course, WhatsApp requires a mobile connection, and anyone who has spent time in Afghanistan knows its complex terrain often times requires multiple forms of communications to reach across the country." WhatsApp spokesperson. Producer: Kate Bissell Researcher: Anna Miles

Aleks Krotoski explores the relationships between social media content creators and their audience, asking how does it get complicated when money starts to change hands. These are often described as para-social relationships. Ones were the audience knows a lot about the content creator and they know next to nothing about the viewers. This can lead to misunderstandings and even behaviours that border on coercive control. How can this new breed of celebrity navigate this world when what their subscribers are paying for is their own piece of them? Producer: Peter McManus