“A political event was that I met Fidel Castro, the Cuban revolutionary. He is a young, intelligent guy, very sure of himself and extraordinarily audacious; I think we hit it off well.”

“Above all, always be capable of feeling deeply any injustice committed against anyone, anywhere in the world. This is the most beautiful quality in a revolutionary.”

“Cruel leaders are replaced only to have new leaders turn cruel.”

“How easy it is to govern when one follows a system of consulting the will of the people and one holds as the only norm all the actions which contribute to the well being of the people.”

“I am one of those people who believes that the solution to the world's problems is to be found behind the Iron Curtain.”

“I could become very rich in Guatemala but by the low method of ratifying my title, opening a clinic, and specialising in allergies. To do that would be the most horrible betrayal of the two 'I's' struggling inside me: the socialist and the traveller.”

“I had a project for my life which involved 10 years of wandering, then some years of medical studies and, if any time was left, the great adventure of physics.”

“I have a wish. It as a fear as well - that in my end will be my beginning.”

“I know you are here to kill me. Shoot, coward, you are only going to kill a man.”

“I would probably have more in common with a whale than with a bourgeois married couple employed at worthy institutions that I would wipe from the face of the earth if it was given to me to do so.”

“If you tremble with indignation at every injustice, then you are a comrade of mine.”

“It is important to emphasize that guerrilla warfare is a war of the masses, a war of the people. The guerrilla band is an armed nucleus, the fighting vanguard of the people. It draws its great force from the mass of the people themselves.”

“It is unnecessary to say that Fidel Castro possesses the high qualities of a fighter and statesman: our path, our struggle, and our triumph we owed to his vision.”

“Many will call me an adventurer - and that I am, only one of a different sort: one of those who risks his skin to prove his platitudes.”

“Passion is needed for any great work, and for the revolution, passion and audacity are required in big doses.”

“Remember that the revolution is what is important, and each one of us, alone, is worth nothing.”

“Silence is argument carried out by other means.”

“Study hard so that you can master technology, which allows us to master nature.”

“The guerrilla fighters should be required to go to bed and get up at fixed hours. Games that have no social function and that hurt the morale of the troops and the consumption of alcoholic drinks should both be prohibited.”

“The only passion that guides me is for the truth... I look at everything from this point of view.”

“The peasant must always be helped technically, economically, morally and culturally. The guerrilla fighter will be a sort of guiding angel who has fallen into the zone, helping the poor always and bothering the rich as little as possible in the first phases of the war.”

“The revolution is not an apple that falls when it is ripe. You have to make it fall.”

“The true revolutionary is guided by a great feeling of love. It is impossible to think of a genuine revolutionary lacking this quality.”

“We cannot be sure of having something to live for unless we are willing to die for it.”

“Whenever death may surprise us, let it be welcome if our battle cry has reached even one receptive ear and another hand reaches out to take up our arms.”