Remo's Reviews > ¿Cómo Se Llama Este Libro?: El Enigma de Drácula y Otros Pasatiempos Lógicos

A primera vista es un libro de pasatiempos, puzzles matemáticos y en general entretenimiento inteligente. Pero es algo más. Sí, hay acertijos de lógica y hay pasajes divertidos. Pero hay aún algo más. A medida que vamos resolviendo problemas que nos plantean vampiros que solo dicen la verdad, o que solo mienten, o que pueden hacer una cosa u otra, vamos apreciando el mensaje de fondo que nos transmite el autor, sobre la Lógica como fundamento de las Matemáticas. Es un libro de filosofía de las matemáticas disfrazado de vampiro que siempre miente o siempre dice la verdad. Es una lectura nada ligera, que requiere sentarse con lápiz y papel para sacar algunos de los acertijos (otros ni con eso), y estar dispuesto a echarle unas pensadas. No es un entretenimiento ligero. Es un aprendizaje con entretenimiento. Otros, sin embargo (y hay muchas decenas) só son divertidos y sencillos. El libro tiene suficiente para todo tipo de públicos.

De los primeros problemas:

My introduction to logic was at the age of six. It happened this way: On April 1, 1925, 1 was sick in bed with grippe, or flu, or something. In the morning my brother Emile (ten years my senior) came into my bedroom and said: "Well, Raymond, today is April Fool's Day, and I will fool you as you have never been fooled before!" I waited all day long for him to fool me, but he didn't. Late that night, my mother asked me, "Why don't you go to sleep?" I replied, "I'm waiting for Emile to fool me." My mother turned to Emile and said, "Emile, will you please fool the child!" Emile then turned to me, and the following dialogue ensued:

Emile: So, you expected me to fool you, didn't you?

Raymond: Yes.

Emile: But I didn't, did I?

Raymond: No.

Emile: But you expected me to, didn't you?

Raymond: Yes.

Emile: So I fooled you, didn't I!

Well, I recall lying in bed long after the lights were turned out wondering whether or not I had really been fooled. On the one hand, if I wasn't fooled, then I did not get what I expected, hence I was fooled. (This was Emile's argument.) But with equal reason it can be said that if I was fooled, then I did get what I expected, so then, in what sense was I fooled. So, was I fooled or wasn't I?

I shall not answer this puzzle now; we shall return to it in one form or another several times in the course of this book. It embodies a subtle principle which shall be one of our major themes.