Science is a human activity, and the best way to understand it is to understand the individual human beings who practise it. Science is an art form and not a philosophical method. The great advances in science usually result from new tools rather than from new doctrines. ... Every time we introduce a new tool, it always leads to new and unexpected discoveries, because Nature's imagination is richer than ours.
Imagination is as vital to any advance in science as learning and precision are essential for starting points. Let me warn you to beware of two opposite errors: of letting your imagination soar unballasted by facts, but on the other hand, of shackling it so solidly that it loses all incentive to rise.
Certain elements of today's ecological crisis reveal its moral character. First among these is the indiscriminate application of advances in science and technology. Many recent discoveries have brought undeniable benefits to humanity. Indeed, they demonstrate the nobility of the human vocation to participate responsibly in God's creative action in the world. Unfortunately, it is now clear that the application of these discoveries in the fields of industry and agriculture have produced harmful long-term effects.
All revolutionary advances in science may consist less of sudden and dramatic revelations than a series of transformations, of which the revolutionary significance may not be seen (except afterwards, by historians) until the last great step. In many cases the full potentiality and force of a most radical step in such a sequence of transformations may not even be manifest to its author.