In 1924, Krutch became theater critic for The Nation, a position he held until 1952.[1]:131 As an author, Krutch first achieved prominence when he published The Modern Temper in 1929. There he challenged then-fashionable notions of scientific progress and optimism, arguing that science leads logically to a bleak view of the human condition.[5]:319 In the 1940s he wrote widely read biographies of Samuel Johnson and Henry David Thoreau and—largely inspired by Thoreau—published his first nature book, The Twelve Seasons (1949).