But now science is the belief system that is hundreds of years old. And, like the medieval system before it, science is starting not to fit the world any more. Science has attained so much power that its practical limits begin to be apparent. Largely through science, billions of us live in one small world, densely packed and intercommunicating. But science cannot help us decide what to do with that world, or how to live. Science can make a nuclear reactor, but it cannot tell us not to build it. Science can make pesticide, but cannot tell us not to use it. And our world starts to seem polluted in fundamental ways — -air, and water, and land — -because of ungovernable science.

The limits of science have always been the source of bitter disappointment when people expected something from science that it was not able to provide. Take the following examples: a man without faith seeking to find in science a substitute for his faith on which to build his life; a man unsatisfied by philosophy seeking an all-embracing universal truth in science; a spiritually shallow person growing aware of his own futility in the course of engaging in the endless reflections imposed by science. In every one of these cases, science begins as an object of blind idolatry and ends up as an object of hatred and
contempt. Disenchantment inevitably follows upon these and similar misconceptions. One question remains: What value can science possibly have when its limitations have become so painfully clear?

Science is far from a perfect instrument of knowledge. It's just the best we have. In this respect, as in many others, it's like democracy. Science by itself cannot advocate courses of human action, but it can certainly illuminate the possible consequences of alternative courses of action.

But doing so, controlling our own fate, requires that a large fraction of us understand and appreciate science: How it operates. What it teaches us about the universe, the Earth, and life. What it can achieve. What its limitations are, due to inadequate knowledge or technology. How those limitations may be overcome. How we transition from speculation to educated guess to truth. How extremely rare are revolutions in which our perceived truth changes, yet how very important. I hope this book contributes to that understanding.

the responsibility of science, and the limits of technological progress.

[Science] works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are
worthless. Second: whatever is inconsistent with the facts must be discarded or revised. We must understand the Cosmos as it is and not confuse how it is with how we wish it to be. The obvious is sometimes false; the unexpected is sometimes true.

Science can heal, or science can kill. It depends on the soul of the man using the science.

The aim of science is not to open the door to infinite wisdom, but to set a limit to infinite error.

All this attempt to control... We are talking about Western attitudes that are five hundred years old... The basic idea of science - that there was a new way to look at reality, that it was objective, that it did not depend on your beliefs or your nationality, that it was rational - that idea was fresh and exciting back then. It offered promise and hope for the future, and it swept away the old medieval system, which was hundreds of years old. The medieval world of feudal politics and religious dogma and hateful superstitions fell before science. But, in truth, this was because the medieval world didn't really work any more. It didn't work economically, it didn't work intellectually, and it didn't fit the new world that was emerging... But now... science is the belief system that is hundreds of years old. And, like the medieval system before it, science is starting to not fit the world any more. Science has attained so much power that its practical limits begin to be apparent. Largely through science, billions of us live in one small world, densely packed and intercommunicating. But science cannot help us decide what to do with that world, or how to live. Science can make a nuclear reactor, but it can not tell us not to build it. Science can make pesticide, but cannot tell us not to use it. And our world starts to seem polluted in fundamental ways - air, and water, and land - because of ungovernable science... At the same time, the great intellectual justification of science has vanished. Ever since Newton and Descartes, science has explicitly offered us the vision of total control. Science has claimed the power to eventually control everything, through its understanding of natural laws. But in the twentieth century, that claim has been shattered beyond repair. First, Heisenberg's uncertainty principle set limits on what we could know about the subatomic world. Oh well, we say. None of us lives in a subatomic world. It doesn't make any practical difference as we go

Scientists have power by virtue of the respect commanded by the discipline... We live with poets and politicians, preachers and philosophers. All have their ways of knowing, and all are valid in their proper domain. The world is too complex and interesting for one way to hold all the answers.

science can only take you so far and then you have to leap

We believe that it is possible for scientific work to gain some knowledge about the reality of the world, by means of which we can increase out power and in accordance with which we can arrange our life. If this belief is an illusion, then we are in the same position as you. But science has given us evidence by its numerous and important successes that it is no illusion.

Science not only describes, it predicts. It deals not only with the past but with the future. Nor is prediction the last word: to the extent that relevant conditions can be altered, or otherwise controlled, the future can be controlled. If we are to use the methods of science in the field of human affairs, we must assume that behavior is lawful and determined. We must expect to discover that what a man does is the result of specifiable conditions and that once these conditions have been discovered, we can anticipate and to some extent determine his actions.

Science tells us what we can know, but what we can know is little, and if we forget how much we cannot know, we become insensitive to many things of great importance.