Abstract
The value of the library as a receiver of the universal knowledge is treated in Ibis article. In his continuous walking around the libraries in Mexico and the whole world the author highlights the educational and formative role of those cultural institutions. From the modest libraries of elementary studies to the professional and efficient national institutions, the library influences the intellectual, moral, and spiritual formation of those who visit their collections. Library Miguel Lerdo de Tejada is particularly admirable, because with just a few resources it offers the user a complete collection of books about legislation, historiography, Greek and Latin classics, works on philosophy, theology and others in equal value and interest.