"Knowledge" is one of those interesting concepts; it is something for which all humanity strives. Unfortunately, it is quite a vague idea. What exactly is knowledge anyway? Is it an unchanging body of "facts"? Russell says that theological dogmas are fixed, and regarded by the orthodox as incapable of improvement; even some philosophers have tried to take this route. I’m sure this is true with many. A closed mind is not desirable. Ideas should always be open to change, provided proper logic and evidence demonstrate the need for the change. Is knowledge ultimately amenable to future discovery through the scientific method? Is the scientific method the only proper means of finding knowledge? Is there value to knowledge alone, or is it valuable only as it becomes a means for further purposes? In this paper, I wish to consider some of the facets concerning the philosophical questions of knowledge and science, particularly as they touch upon "common sense."

How do we know that we know anything? What real proof do we have that we have any certain knowledge? We operate on a day-to-day basis with the assumption that we have knowledge. Those activities in which we engage without thinking them through, such as tying our shoes and brushing our teeth, are based upon knowing how to do them. At least we are convinced that we know how to do certain things. By our actions in practical living, we show that we assume the reality of objects, such as tables and chairs. We "know" that these objects are real; when we sit down on a chair, for example, we trust that the chair will hold us up. We do not think in terms of falling through objects as if they were mere appearances with no real substance. Though skeptics and those who argue against common sense may question our knowledge of the reality of these, the fact remains that this is the way we live. To live otherwise would be considered unreasonable by the vast majority of people, even if they are thought to be ignorant.

Even those who argue against common sense live in a way that reflects the common sense view of objects. Imagine what life would be like if we did not trust that things are as they appear to be. We would be considered paranoid and mentally unsound if we did not trust that objects are as they seem to be. We would be afraid to sit down or even walk anywhere because we could not know if chairs or walls were real objects. In Against Common Sense, Russell argues that "we all feel quite sure about these in ordinary life, and yet our reasons for confidence are really very inadequate." This demonstrates the point. We live in a practical way, even though there may be philosophical questions about the reality of objects. For this reason, the common sense approach is much more practical in life than is the view against common sense. Perhaps common objects are not what they really appear to be. Maybe they are what physics claims — just a vast system of electrons and protons in rapid motion with empty space between. Now what do we do with this knowledge? What kind of practical effect will it have on our lives? Even if we do become "less cocksure as we become more accurate," we must live with an a priori belief system that supposes that most objects are indeed what they appear to be.

Knowledge is based upon memory. If we cannot remember anything that we have learned, then we will not really "know" anything. Sadly, memory is often very fallible; and this fact alone brings much knowledge into question. This is one reason why records of past events and experiments are so important. If we record something as we learn it, then we do not have to rely as much upon personal memory. Russell points out that no direct confirmation of a belief about the past is possible. This is true. When it comes to matters of history, we all utilize a form of "faith." Because historical matters cannot be directly confirmed, then there is always a possibility of doubt about what we think we know. How do we know, for example, that Abraham Lincoln was president during the Civil War, or that there even was a Civil War for that matter? We look at records of the past, the testimony of those who were there, and we trust the general methods of history. Still, is it possible that we really don’t know these things for sure? Is it possible that the whole matter was concocted by a bunch of frauds? Perhaps people just didn’t remember times and events properly.

I don’t see the need to go into such skepticism. Empiricism is concerned with what can be perceived through our senses. If taken too far, however, it results in a disintegrating and destructive skepticism. I believe this was the situation with Hume. Empiricism has its place, to be sure, but I wouldn’t completely count out rationalism either. I am often a skeptic myself, but if we are not careful, we may just hit a pessimistic wall of philosophical uncertainty. I don’t see the practical need for taking it to that extreme.

Perceptual observation is, I believe, the best method for knowing something with as much certainty as is possible. First-hand observation may be preferred above all other methods of obtaining knowledge. However, it is impossible for any one person to experience all that can be experienced. No scientist can test every possible object in the universe. For this reason alone, the scientific method is limited in what it can accomplish. Further, even if a scientist is able to come to some conclusions about particular objects, how do I know that it is right if I did not see it first-hand? What if my first-hand observations differ, though I may not be as scientifically technical about my observations? Still, I have to deal with reality as I see it; but if I am to be considered a reasonable person at all, then I will also have to accept first-hand testimony of credible witnesses of events. This is true whether the event be contemporary or historical. Someone, somewhere, saw these events with their own senses. They could be mistaken; they might embellish, but they are giving things out as they saw through their own observations. This is the only way it can be.

I wish to comment upon the three observations made by Murphy concerning perceptual observation. First, I agree with the idea that it is fallible. While we generally trust that the things we see, hear, and touch are what they really are, there are many times when our senses have been mislead. There are times when I think that I hear something loud and clear, whereas no one else within the same proximity heard it. I may think that I see something, and am convinced in my mind that it is what I thought, but then find that it was something entirely different. Thus, while I may think that I know something based upon my perception, there is a possibility that I perceived something incorrectly. This is one reason why many witnesses to a given event are important to establish a case. In a court of law, for example, the more credible witnesses that exist who can establish alibis or guilt, the better the case. One witness, all alone, might be mistaken. Perception is fallible, and this is why it is best to continually re-evaluate what we think we know.

The second point grows naturally out of the first. Perceptual observation is corrigible, open to change and correction. As we continue to perceive and carefully observe the many objects and events around us, we should be open to the possibility of correcting what we think we already know. Perhaps something else will be discovered that will change the generally understood knowledge. Images can become sharper in our minds; old thoughts may give way to new thoughts as new information is understood. This is how progress is made. Again, however, one need not run to extremes. Virtually anything can be questioned in terms of its reality. One can raise so many unanswerable questions that life becomes a meaningless mass of confusion. In a court of law, a person is convicted when the jury is convinced "beyond a reasonable doubt." This is the way we live life. There may be doubts, but are they reasonable? Is it reasonable, for example, to doubt whether or not I am actually writing on a computer and sitting at a chair? Is there anything meaningful that will come from such questioning? While we should always be open to change, the change should be demonstrated to be reasonable. Rational thought must interact with perceptual observation.

The third point relative to this discussion is that perceptual observation is our only ultimate source of information; there is really no other way of learning. The only way that I can learn something is to hear it, observe it, or physically and mentally interact with in some fashion. I am a Christian, for example, but I do not believe that God zaps knowledge into anyone’s mind, contrary to what some have claimed. I believe we learn truth just as anyone else. We learn it through a process of hearing and observing. However, I also believe that there is more to reality than what we can observe and hear. I agree with the idea that there may be "much more in reality ... than perceptual observation can disclose, but there cannot be less." I do not think that some would take it as far as I would, though. I do not believe that we can rationally say that nothing exists outside of what our senses can pick up. How can we possibly know that? While I agree that perceptual observation is the best method of gaining knowledge, I do not believe that all truth and knowledge necessarily lies within the realm of our senses. In other words, there may be many things that exist far beyond our ability to know or comprehend. If we cannot establish that we have all knowledge when it comes to things that we can perceive with our senses, then how can we possibly argue that we know that nothing outside of these senses exists? My concern, however, is with what I can know; and I can only know things through my physical and mental faculties.

As we observe and learn, I think that it is important to understand that there is a difference between "facts" and the interpretations that are given to the facts. We may think that someone’s particular interpretation is factual, but the facts themselves may also be interpreted differently. For example, if I find a heap of bones on a hill, I might say that there must have been some animals fighting one another. Someone else may conclude that these were animals trying to escape flooding waters. The fact is that there are bones in a heap; the interpretations as to how they got there and other relevant questions may indeed differ. I need to make sure that I don’t press the interpretation to the same level as the fact itself.

Science is, by its very nature, limited to that which can be tested in a controlled atmosphere, observed, and repeated for clarified observation. Further, the scientific method is limited in that it is non-moral. It is not equipped to deal with morality; the method itself cannot make value judgments. Neither can it deal with unique, historical events. There may be events analogous to those in the past, but historical events cannot be repeated for our observation. Science can only give us information in the present. I know that sounds strange, but the fact is that any evidence we have for the past only exists now in the present. We might be able to test certain objects that relate to the past, but whatever we are able to test and observe is only going to be done in the present. I believe that we can "know" historical events and people through ordinary means of learning. People in the past saw, heard, felt, and recorded the events that they encountered. If considered to be credible, then we may decide that we can accept that a certain person lived, or that certain events occurred. In other words, we accept testimony of the past on the same grounds that we accept testimony in the present. I cannot observe everything myself, so I have to trust that others have correctly observed and sensed what they know.