In 1912 Georg Pauli painted Mens sana in corpore sano, a mural painting in al secco technique at Per Brahegymnasiet in Jönköping. The outcome of the painting caused a lot of different reactions, many people found it strange and bad and criticized it harshly. As a student myself at the school many years later, I found the painting a bit weird, and later in life during my studies in art history I became interested in Mens sana in corpore sano and why it looks like it does. In this study, I have seeked to understand the painting and its context. I have analyzed the motive according to Erwin Panofskys iconological method, to see what the three levels means. For the context of the paining, I give a presentation of mural painting both in schools and society during 1910s, Pauli as a painter and author, and his relation to cubism. I will also present how others have been writing about and interpretating Mens sana in corpore sano over the years since the painting was created 1912 to 2024.