Quotes from Steven Weinberg

It seems to me that to understand these early Greeks, it is better to think of them not as physicists or scientists or even philosophers, but as poets.

There is an important feature of modern science that is almost completely missing in all the thinkers I have mentioned, from Thales to Plato: none of them attempted to verify or even (aside perhaps from Zeno) seriously to justify their speculations. In

El gran éxito de Newton consistió en explicar los movimientos de los planetas, no simplemente en describirlos. Newton no explicó la gravitación, y sabia que no lo había hecho, pero es lo que ocurre siempre con las explicaciones, que siempre queda algo para una futura explicación.

The appearance of fine-tuning in a scientific theory is like a cry of distress from nature, complaining that something needs to be better explained.

The theologian Paul Tillich once observed that among scientists only physicists seem capable of using the word "God" without embarrassment. Whatever one's religion or lack of it, it is an irresistible metaphor to speak of the final laws of nature in terms of the mind of God.

This is often the way it is in physics. Our mistake is not that we take our theories too seriously, but that we do not take them seriously enough. It is always hard to realize that these numbers and equations we play with at our desks have something to do with the real world.

much of the writing of physicists barely reaches the level of prose.

The value today of philosophy to physics seems to me to be something like the value of early nation-states to their peoples. It is only a small exaggeration to say that, until the introduction of the post office, the chief service of nation-states was to protect their peoples from other nation-states. The insights of philosophers have occasionally benefited physicists, but generally in a negative fashion—by protecting them from the preconceptions of other philosophers.

In a famous article,8 the physicist Eugene Wigner has written of "the unreasonable effectiveness of mathematics.

There is a beauty in these laws that mirrors something that is built into the structure of the universe at a very deep level

Itwas one time when people thought the value of the fine structure constant wasimportant. Now of course it's still important, of course, as a practical matter,but we now know that the value it has is a function, that in any fundamental theory you derive the fine structure constant as a function of all sorts of mass ratios and so on, and it's not really that fundamental.

Descartes y Bacon son solo dos de los filósofos que a lo largo de los siglos intentaron formular reglas para la investigación científica, algo que nunca funciona. Aprendemos a practicar la ciencia no imponiendo reglas acerca de cómo practicarla, sino a partir de la experiencia de trabajar en ella, impulsados por la satisfacción que obtenemos cuando nuestros métodos consiguen explicar algo.

But every once in a while someone finds a way of explaining some phenomenon that fits so well and clarifies so much that it gives the finder intense satisfaction, especially when the new understanding is quantitative, and observation bears it out in detail. Imagine

Nos proporciona un intenso placer conseguir explicar algo con éxito, al igual que cuando Newton explicó las leyes del movimiento planetario de Kepler, junto con otras muchas cosas. Las teorías y los métodos científicos que sobreviven son aquellos que proporcionan esa satisfacción, encajen o no con ningún modelo preexistente sobre cómo habría que practicar la ciencia.

Ni en el mundo antiguo ni en el medieval se concebía como una meta nada parecido a la ciencia moderna. De hecho, si nuestros predecesores pudieran haber imaginado la ciencia como es en la actualidad, no les habría gustado mucho. La ciencia moderna es impersonal, no deja espacio a la intervención sobrenatural ni a los va lores humanos; no tiene ningún propósito, y tampoco ofrece esperanzas de certezas.

I have in mind here poetry in a broader sense: language chosen for aesthetic effect, rather than in an attempt to say clearly what one actually believes to be true.

We on earth do not feel either the gravitational field of the sun or the centrifugal force caused by the earth's motion around the sun because the two forces balance each other, but this balance would be spoiled if one force was proportional to the mass of the objects on which it acts and the other was not; some objects might then fall off the earth into the sun and others could be thrown off the earth into interstellar space.

Todo es impredecible y no obedece a ningún plan, pero conduce a un conocimiento fiable, y disfrutamos al andar el camino.

What is important in science (I leave philosophy to others) is not the solution of some popular scientific problems of one's own day, but understanding the world. In the course of this work, one finds out what sort of explanations are possible, and what sort of problems can lead to those explanations. The progress of science has been largely a matter of discovering what questions should be asked.

When you say anything controversial, you are likely to be blamed not so much for what you have said as for what people think that someone who has said what you said would also say.

Finally, there is a more subtle relation among F, E, and V.

The pre-Socratic Xenophanes famously commented, "Ethiopians have gods with snub noses and black hair, Thracians gods with gray eyes and red hair," and remarked, "But if oxen (and horses) and lions had hands or could draw with hands and create works of art like those made by men, horses would draw pictures of gods like horses, and oxen of gods like oxen, and they would make the bodies [of their gods] in accordance with the form that each species itself possesses.

I chose "Discovery" instead of "Invention" to suggest that science is the way it is not so much because of various adventitious historic acts of invention, but because of the way nature is. With all its imperfections, modern science is a technique that is sufficiently well tuned to nature so that it works—it is a practice that allows us to learn reliable things about the world. In this sense, it is a technique that was waiting for people to discover it.

energy of any sort generates gravitational fields and is in turn acted on by gravitational fields, so an energy filling all space could have important effects on the expansion of the universe.