In his book "The Tipping Point," Malcolm Gladwell discusses the concept of the neocortex ratio in relation to Homo sapiens, which links our brain's size to social relationships. He determines that this ratio suggests an optimal group size of about 150 individuals, which is the upper limit for maintaining meaningful social connections. This number reflects the ability to know people personally and understand their interactions with us.

Gladwell's findings imply that beyond this group size, maintaining such deep social relationships becomes challenging, potentially leading to a breakdown in community ties. The figure of 150, therefore, highlights the importance of close-knit social networks in human interactions and the natural limits of our social capacities.