But in introducing me simultaneously to skepticism and to wonder, they taught me the two uneasily cohabiting modes of thought that are central to the… - Carl Sagan

En el polo opuesto de la discusión, la frase -derecho a la vida- constituye un ejemplo claro de expresión altisonante concebida para impresionar más que para aclarar las cosas. Ni hoy ni nunca ha existido en ningún país de la tierra el derecho a la vida. Criamos animales domésticos para luego darles muerte, destruimos los bosques, contaminamos ríos y lagos hasta causar la muerte de toda la fauna piscícola, cazamos venados por deporte, leopardos por la piel y ballenas para preparar comida para los perros, atrapamos a los delfines, boqueantes y semiasfixiados, con grandes redes del tipo utilizado para la pesca del atún, y senteciamos a muerte a los perros cachorros para -equilibrar la población-. Todos estos animales y vegetales están tan vivos como nosotros. Lo que muchas sociedades humanas protegen no es la vida, sino la vida el hombre, y aún así desencadenamos guerras con medios -modernos- que causan estragos a la población civil y que suponen un tributo tan escandaloso que muchos de nosotros ni siquiera nos atrevemos a entrar en su consideración.

The neutrons, as we have said and as their name suggests, carry no electrical charge. The protons have a positive charge and the electrons an equal negative charge. The attraction between the unlike charges of electrons and protons is what holds the atom together. Since each atom is electrically neutral, the number of protons in the nucleus must exactly equal the number of electrons in the electron cloud. The chemistry of an atom depends only on the number of electrons, which equals the number of protons, and which is called the atomic number. Chemistry is simply numbers, an idea Pythagoras would have liked. If you are an atom with one proton, you are hydrogen; two, helium; three, lithium; four, beryllium; five, boron; six, carbon; seven, nitrogen; eight, oxygen; and so on, up to 92 protons, in which case your name is uranium.

But before the grandeur and intricacy of Nature, he was, like Ptolemy and Kepler, exhilarated as well as disarmingly modest. Just before his death he wrote: “I do not know what I may appear to the world; but to myself I seem to have been only like a boy, playing on the seashore, and diverting myself, in now and then finding a smoother pebble or a prettier shell than ordinary, while the great ocean of truth lay all undiscovered before me.