What is the 'Dunbar's number' and how does it relate to social groups?

Dunbar's number refers to the cognitive limit to the number of stable relationships a person can maintain, typically estimated to be around 150. The host explains that our social interactions and the need for validation are influenced by this number. As social beings, we seek approval and acceptance from our social groups, and being excluded can feel like a threat to our survival. Understanding this concept can help individuals navigate their social relationships and the pressures of social acceptance.