What did Descartes know for certain? That he is a thinking thing, a cogito. But what does it mean to think? Descartes lists a few modes of thinking: Doubting, affirming, denying, understanding.Heidegger embarks upon a similar project to Descartes. What, he asks, is the fundamental nature of our experience? Of our existence? Heidegger agrees with Descartes. If we want to live life well we need to be clear about its most fundamental components. Descartes answer is summarised by his phrase cogito ergo sum, which translates as thinking, therefore, being. For Heidegger, Descartes has it the wrong way around. He thinks that Descartes has neglected the sum, the being. What is it to be something? Heidegger’s answer comes in a number of forms: he says as well as being thinking things we have care for things, we have an anxiety about the world, we are existential, but most importantly, we are beings-in-the-world.Then & Now is FAN-FUNDED! Support me on Patreon and pledge as little as $1 per video: http://patreon.com/user?u=3517018