Book excerpt: Sharing stories and advice rooted in the science of evolutionary psychology, father and son authors Doug Kenrick and David Lundberg-Kendrick pinpoint the dangers of stone-age problem solving for our lives today, and present a new, systematic way to survive and be happy in the modern world. Over millennia, we humans have evolved a set of motivational systems to help us solve the seven basic problems of existence: surviving, protecting ourselves from attackers, forming friendships, winning respect, attracting mates, hanging onto mates, and caring for our families. We seek the same goals in the 21st century. However, the saber-tooth tigers and rival tribes that once threatened us have been replaced by marketers peddling sugar-laden foods, pundits fanning the culture war flames, and payday loan companies scamming those who can least afford it. Through a series of engaging narratives and science-based life tips, this book helps us see past our electronics and lattes and gain helpful insights into achieving the life we want.