The Library of Mistakes is a charitable venture (registered charity SC040205) founded to promote the study of financial history. In recent years, financial education has focused on the power of the equation to explain economic and financial forces. This distillation of complex forces into faux objectivity has created dangerous errors in financial understanding. That objectivity has only been attained with the use of assumptions which do not hold in the real world. The Library of Mistakes exists to allow students, professionals and members of the general public to study financial history to understand how finance has worked, rather than how it should work if key unrealistic assumptions are made. If Einstein is right and the sign of madness is to do the same thing over again expecting a different result, then a study of financial history may help to reduce financial madness. By studying financial history we hope to improve financial understanding one mistake at a time.