Spiritism is often talked about but rarely explained clearly — and much of what people think they know is shaped by prejudice, caricature, or confusion with unrelated practices. This introductory course sets the record straight by going back to the source: "The Spirits' Book" (O Livro dos Espíritos), codified by Allan Kardec in 1857. The goal is simple — to promote an honest, respectful understanding of the Spiritist doctrine in its three inseparable aspects: religious, philosophical, and scientific. You start with the foundations: who Allan Kardec was, how the doctrine came to be codified through the systematic study of mediumship, what Spiritism actually claims (and what it does not), and why it presents itself as much a field of study as a faith. From there you examine the doctrine's answers to the great questions of existence — the nature of God and the primary causes of the universe, the origin and destiny of the soul, and the relationship between spirit and matter. You then explore the spirit world: what spirits are, the idea of reincarnation and successive lives, the plurality of inhabited worlds, and the law of progress that, in the Spiritist view, governs the evolution of every soul. The heart of the course is the moral law — the practical ethics Kardec drew from the Gospel, summarized in charity, love of neighbor, and personal responsibility for one's own progress. Finally you turn to the doctrine's message of hope: its view of life after death, of suffering and consolation, and of the future that awaits the spirit. Throughout, the tone is educational and non-dogmatic: this is a course to understand Spiritism, weigh its ideas thoughtfully, and set aside prejudice — whatever you personally choose to believe.