In fact, what we are can only be attributed for a small part to our labour and personal individuality, because we owe it almost entirely to our forefathers, both of blood and mind.

We are intelligent beings: intelligent beings cannot have been formed by a crude, blind, insensible being: there is certainly some difference between the ideas of Newton and the dung of a mule. Newton's intelligence, therefore, came from another intelligence

All human thought, including scientific thought, rests on premises which cannot be validated by human reason and which came from historical epoch to historical epoch.

We are inescapably the result of a long heritage of learning, adaptation, mutation and evolution, the product of a history which predates our birth as a biological species and stretches back over many thousand millennia... Going further back, we share a common ancestry with our fellow primates; and going still further back, we share a common ancestry with all other living creatures and plants down to the simplest microbe. The further back we go, the greater the difference from external appearances and behavior patterns which we observe today.

Los hombres crecieron en los bosques y nosotros les tenemos una afinidad natural. ¡Qué hermoso es un árbol que se esfuerza por alcanzar el cielo!

Evolution is the long blur, a constant and living flow of branching relationships. One thing is always connected to another and another. Having no regard for our love of labels and organization, life rolls on as a continual stream of organic matter. The important thing about the origin of the human brain is not pinpointing some specific time, event, or fossil to declare a beginning in order to satisfy our desire for order. What matters is that we understand the process from which it emerged and how deeply rooted the modern human brain is to its past.

What, unless biological science is a mass of errors, is the cause of human intelligence and vigour? Hardship and freedom: conditions under which the active, strong, and subtle survive and the weaker go to the wall; conditions that put a premium upon the loyal alliance of capable men, upon self-restraint, patience, and decision. And the institution of the family, and the emotions that arise therein, the fierce jealousy, the tenderness for offspring, parental self-devotion, all found their justification and support in the imminent dangers of the young.

Mi padre comenzaba apoyándose en la fuerza de los dos axiomas siguientes: Primero: que, para un hombre, una onza de su propia inteligencia valía por una tonelada de la de cualquier otra persona; y Segundo (el cual, por cierto, era el fundamento del primer axioma — aunque viniera después): que la inteligencia de todo hombre debía necesariamente provenir de su propia alma — y jamás de la de ninguna otra persona.

If each one of us adds something to the common weal in the domain of science, or art, or morality, the reason is because long series of generations have lived, worked, thought, and suffered before us. The science which you honour to-day has been created by the patient labours of our predecessors.

At some point, human intelligence became collective and cumulative in a way that happened to no other animal.

Los dioses no vienen a componer las cosas que nos salieron mal. Fíjese en la historia del hombre, y se dará cuenta de que siempre estuvimos solos

Cuando los hombres descubren algo nuevo sienten una inclinación natural a hacer uso de ello, probablemente en respuesta a sus circuitos cerebrales. Esa extraña proclividad, que no comparten de modo sistemático las demás bestias o plantas de la Tierra, constituye tanto una causa principal del éxito humano como un motivo básico de que estemos despojando una parte tan considerable de la superficie terráquea. Las aves saben, mejor que los humanos, que no deben ensuciar su nido.

I wish I could have told him that loneliness is a human invention. Trees are never lonely. Humans think they know with certainty where there being ends and someone else's starts. With there roots tangled and caught up underground, linked to fungi and bacteria, trees harbour no such illusions. For us, everything is interconnected.

The evolution of scientific thought is inseparable from the history of man's efforts to resolve the perplexities of his own existence.