Everywhere you go, you generate a cloud of data. You're trailing data, everything that you do is producing data. And then there are computers looking at that data that are learning, and these computers are essentially trying to serve you better. They're trying to personalize things to you. They're trying to adapt the world to you. So on the one hand, this is great, because the world will get adapted to you without you even having to explicitly adapt it. There's also a danger, because the entities in the companies that are in control of those algorithms don't necessarily have the same goals as you, and this is where I think people need to be aware that, what's going on, so they can have more control over it.
We came into this new world thinking that we were users of social media and search engines. It didn't occur to us that social media and search engines were actually using us.

Everyone always wants to be able to choose - but who really makes these choices? And do we really want to have more choices? Michael Stevens finds out as he explores decision-making.

When it comes to illusions, optical illusions get all the attention. But the whole body you have can be fooled and can fool the brain. What is touch? Is it real, or is it just in our heads? Michael Stevens decides to find out.

Who are you? Do you even know who you are? Are you your memories? Are you the choices you make? Are you you? Or are you someone else, but manipulated to be you? If you can lose track of your past and your memories can be altered or implanted, in the end, who are you really? Michael Stevens finds out as he explores what makes you you.

This episode looks at a group of black survivalists. British Buzzfeed correspondent Bim Adewunmi looks at an unusual group of doomsday preppers who don't fit the normal stereotype for that group. She interviews people of color who train themselves to prepare for disaster.

Around the world, food allergies are surging to near-epidemic levels. Medicine is just beginning to understand why some people react to seemingly harmless foods. Scientists race to understand what's changed in our bodies, while farmers and chefs contend with new challenges.