“When we are alone, we are not destroyed by things.” This is a bestseller by philosopher Kiyoshi Miki, who affirmed solitude, and a collection of philosophical essays that examine life through 23 points. The book contains over 40 instances of the word "solitude," including the section "On Solitude," allowing readers to understand how crucial solitude is in life. "On Death," which begins with "Recently, I no longer find death so terrifying," was published in 1937 when Miki was 40 years old. It was published as a standalone book, "Jinseiron Note," by Sogen-sha in August 1941. Despite its complexity, it was widely accepted even then, reaching its third printing by September. In December of the same year, the Pacific War began with the attack on Pearl Harbor, and on September 26, after the Potsdam Declaration was accepted in August 1945, Miki died in prison while detained. It may not be appropriate to read a work from a certain point in time retrospectively through the author's later life, but it is unavoidable for us today, with wars and conflicts occurring worldwide, to read this book while knowing Miki's life. It would not be blasphemous. "Solitude is frightening not because of solitude itself, but rather because of the conditions of solitude." How should we face life, solitude, and others? Let us learn the philosophy of solitude now. Recycled materials will be used.