The Marginalian began as a weekly email to seven friends and grew into one of the most widely read literary blogs on the internet — sustained entirely by reader donations, never by advertising. Popova has written about thousands of books over two decades, but certain titles appear again and again: ones that reckon honestly with mortality, that celebrate scientific wonder without losing the poetry of existence, and that take seriously the question of what it means to live a meaningful life. Her taste is markedly non-self-help; she gravitates toward books that resist easy answers. The books here reflect not a single reading list she has published but the authors and titles she returns to most persistently in her writing — the ones she quotes at length, revisits across years, and calls foundational.