This is what truly separates a science from a ``pseudoscience'', such as extrasensory perception (ESP), astrology, unidentified flying objects (UFOs), pyramid power, etc.; one could in principle prove a particular scientific theory wrong, such as Newton's 2nd law of motion (and indeed it is wrong in certain cases), but one can never prove that your daily horoscope chart was wrong.
It is important though to recognize that the scientific method, and science in general, addresses certain aspects of particular questions, and should not be considered the complete and total answer. As an extreme example, one could scientifically analyze a piece of music by Bach by breaking it up into a series of different types of sound waves. This of course would miss the very essence of what Bach's music is and represents. Another example might be nuclear power - one could study scientifically what nuclear power is in terms of reactions amongst nuclei, but in this case there may be aspects other than purely scientific ones that are more important. As a final example, some important questions, such as ``Does a God exist?'', have very little basis in traditional scientific studies.
The point of the above is that, when science is relevant, it can be invaluable in providing clear, objective facts on a particular issue based on the knowledge available at the time. We must always remember, however, that there are other concerns, such as moral, religious, aesthetic, economic, and political, which often enter into a given question and which can be just as or even more important than the scientific concerns. In the nuclear power debate, science can address questions such as ``What are the dangers of nuclear power?'' and ``How do these dangers compare to other things?''; science cannot and should not answer questions such as ``Should we as a society take this risk?''. Science thus provides a firm basis for tackling controversial and often complicated issues in a highly technical world - the two main goals of this course are to understand some of the scientific principles involved in these questions, and to develop an ability to question and an awareness that there are often no clear ``correct'', absolute answers.