How much longer can we survive with a broken humanity and cracked civilization? Russia's 2022 invasion of Ukraine, the COVID-19 pandemic, climate change, and rogue artificial intelligence dangerously demonstrate how urgent our existential threats are, and how divided we are in facing them. This book proposes the first comprehensive definition and defense of the Personalist Social Contract (PSC) as a common moral language and thus practical path forward to bring together our sciences and societies in shared survival. We talk about rights, but often mean different things, while many simply trample over them in the pursuit of power. The PSC bridges classical and modern philosophy (with neuroscience and political economics) to recover a common conception of the human person, dignity, and rights uniting our diverse cultures and belief systems to effectively and equitably respond to our contemporary crises.