
Fuente: Cartas de Séneca a Lucilio, Carta XXI.
Fuente: Cartas de Séneca a Lucilio, Carta XXI.
En inglés: «It is the individual who is not interested in his fellow men who has the greatest difficulties in life and provides the greatest injury to others. It is from among such individuals that all human failures spring».
Fuente: Carnegie, Dale. How To Win Friends And Influence People. Editor Arthur R. Pell. Edición reeditada, revisada. Editorial Simon and Schuster, 1982. ISBN 9780671723651, p. 55. https://books.google.es/books?id=0KYWs7EdKYMC&pg=PA55&dq=It+is+the+individual+who+is+not+interested+in+his+fellow++spring&hl=es&sa=X&ved=0ahUKEwiNp92Y4bvgAhVI1uAKHQKvCZkQ6AEIKDAA#v=onepage&q=It%20is%20the%20individual%20who%20is%20not%20interested%20in%20his%20fellow%20men%20who%20has%20the%20greatest%20difficulties%20in%20life%20and%20provides%20the%20greatest%20injury%20to%20others.%20It%20is%20from%20among%20such%20individuals%20that%20all%20human%20failures%20spring&f=false En Google Books.
Citas de Álvaro Uribe
Fuente: Frases Alvaro Uribe Velez http://www.youtube.com/watch?v=dgaXZ12ZaV4. Youtube - 20 de junio de 2010
“Las dificultades también pasan, como todo pasa, sin dificultad.”
Voces (1943)
“Una dificultad es una luz. Una dificultad invencible es el sol.”
Fuente: [Ortega Blake] (2013), p. 1235.