So, what IS science? It has been defined many ways, and its meaning has changed with time. Like many words, "science" has more than one proper use, and the word can also be misused. In its most fundamental sense, modern science is a process by which we try to understand how the natural world works and how it came to be that way. It is NOT a process for merely collecting "facts" about, or just describing, the natural world, although such observations do provide the raw material for scientific understanding. Scientific knowledge is the inferences that scientists draw from the data - the models for how things work.
As a process, certain rules must be followed, but there is NO one "scientific method", contrary to its popular treatment in textbooks. The rules of science are intended to make the process as objective as is humanly possible, and thereby produce a degree of understanding that is as close to reality as possible. One constant theme is that there is no certainty in science, only degrees of probability (likelihood), and potential for change. Scientific understanding can always be challenged, and even changed, with new ways of observing, and with different interpretations. The same is true of scientific facts. New tools and techniques have resulted in new observations, someti mes forcing revision of what had been taken as fact in the past. Therefore, unlike mathematics, and contrary to popular perception, in science nothing is ever proven (in the sense of finality or certainty that the word suggests).
Modern science is based upon several underlying assumptions:
2. Humans can accurately perceive and understand the physical universe. In other words, such understanding is possible.
3. Natural processes are sufficient to explain the natural world; non-natural processes are unnecessary.
4. Nature operates the same way everywhere in the universe, and at all times, except where we have contrary evidence.
Modern science has its limitations:
2. The mental processing of our sensory information is unconsciously influenced by previous experiences, which may result in inaccurate or biased perceptions of the world.
3. It is impossible to know if we have observed every possible aspect of a phenomenon, have thought of every possible alternative explanation, or controlled for every possible variable.
4. Scientific knowledge is necessarily contingent knowledge
rather than absolute knowledge:
6. Science, as for any human endeavor, can be done poorly.
7. Science can be misused.
So, if there are so many limitations and uncertainties to science, why is science so useful? It turns out that the limitations are the strengths of science. From the actual use and application of the knowledge of science to real world problems, we have found that scientific knowledge is the most reliable knowledge we have about the natural world. In other words, most of the time, it works! Predictions based on that knowledge are usually confirmed. This has enabled much of our work in space exploration, modern medicine, agriculture and technology to be as successful as it has been, at an ever-increasing rate.