Tom Morris - Philosophy For Dummies

But another tack is possible. Let me try. In the third grade, my teacher once told me that I had a photographic memory. And I still may; I just don’t have same-day service anymore. Actually, I think the film was exposed somewhere along the way. But, surprisingly often, other people still praise my memory. If that’s my answer to the question of how I know memory ever to be reliable, I have a double problem. First, I am still relying on my memory of what people have said about my memory. And second, this will be a good argument only if I have some independent reason to believe that the testimony of other people is sometimes reliable, and that needs to be established on its own merits. In the next section, we see the problem we run into when we try to justify ever relying on testimony.

So here we go. The testimony of others is simply what other people say, and it happens to be your main source of belief about the past. Skepticism asks a simple question: How do you know that testimony is ever reliable? How do you know that what other people tell you is ever the truth? You get nowhere if you reason in a circle and say, “Well, when I was growing up, my parents told me that other people can usually be trusted, except where money and real estate are involved.” You can’t appeal to a special piece of testimony to justify ever believing testimony, or you have reasoned in a tight circle once more, assuming precisely what needs to be proved. The 17th-century English poet Francis Quarles issued this general warning about testimony and rumor: “Let the greatest part of the news thou hearest be the least part of what thou believest, lest the greater part of what thou believest be the least part of what is true.”

But suppose that in response to the skeptic’s question here, you say, “I just recall that many times in the past, what other people have told me has turned out to be true; so the testimony of others is in fact sometimes reliable.” If you reason like that, you are depending on your memory of past reliability for the testimony of others, and the only noncircular argument that you can give for the reliability of that memory appeals to testimony. But if you can know that memory is sometimes reliable only if you can reasonably believe that testimony is, and you can know that testimony is reliable only if you can reasonably believe that memory is, you just have on your hands a bigger circle of reasoning, and thus have gotten nowhere at all. You have not been able to produce a single piece of untainted, pure evidence that either of your distinctive sources of beliefs about the past is ever reliable.

Surely, you might think you’re on better footing when you examine your beliefs about the present. You can be vague about the past. It can be shrouded in the mists of time. But the present stares you in the face.

What are the distinctive sources for your beliefs about the present? Well, hmm. Gee, when you think about it, it seems that most of your beliefs about the present moment, about things going on beyond the purview of your own immediate perception, are based on the testimony of other people and your memory of what they’ve said. That’s how you know about current events around the world: testimony and memory. And you have just seen the wall you run into when you try to produce even a single shred of untainted evidence that either memory or testimony is ever reliable.

But this can get much more immediate. Even the testimony you remember comes initially through the medium of your own original sense experience. And many things that you know about the more immediate present, you know just from your current experience. This is how I know there is a blue cup on my desk and a steel watch with a black strap on my wrist. I see them. Perhaps sense experience can give the direct, provable tie to reality that the skeptic seems to be seeking. But, of course, the skeptic has challenging questions about sense experience as well.

You don’t need the testimony of others to tell you what’s going on in your room or other immediate physical space right now. And I’m the same. I know by sight that my computer monitor is on. I know by sight and touch that the keyboard is working. I can smell the delightful aftershave I just splashed on. I can hear the hum of my printer. And you have your own direct experience of yourself and your environment. A great number of present moment beliefs are just rooted in the immediacy of sense experience. In the first century BCE, the philosopher and poet Lucretius asked: “What can give us surer knowledge than our senses? With what else can we better distinguish the true and the false?” Our functioning senses and the sense experiences they yield provide our most basic ways of gathering any information about the world around us.

The skeptic, of course, wants to ask, “How do we know that sense experience is ever reliable?” You could see that one coming a mile away, at least if you can trust your own inferences. And what is the answer to the skeptic here? You may be tempted to say, “Look, I recall many times in the past seeming to see something, like a penny on the street, and when I got closer, there it was, just as it had appeared to be. So sense experience is sometimes reliable.”

This is almost embarrassing. First, if you think or say this, you are simply making use of your memory of a past experience. But, as you see in the preceding section on memory, nobody can come up with any good evidence that memory is ever reliable. Forget that for a moment, though, for the sake of argument. The little sample story suggested for you in the previous paragraph just recounted a memory of one initial sense experience that was later confirmed by what exactly? Another memory of another sense experience! So you confront the bane of circular reasoning again. If all sense experience has been called into question by the skeptic, it’s not sufficient for you to answer the challenge by appealing to a particular piece of sense experience, all of which is in question, and especially using memory, which has also been called into question.

Things are looking bad, so to speak. But that appearance might itself be deceiving, so hang in there. If you continue to read on in the coming paragraphs of this chapter, I promise that things are going to seem to get much worse for a few minutes, and then you’ll be truly amazed at what happens. Astonished. Shocked. You’re skeptical? Trust me. Aren’t you almost afraid to peek at beliefs about the future?

Here’s a relief. You don’t even have to go to any particular trouble to consider the reliability of distinctive beliefs about the future, because the same reasoning applies. You form such beliefs based on the past and present. And since you are realizing now that you can’t come up with any good reason for trusting the sources for your beliefs about the past and present, that just transfers over to an equal lack of justification for trusting any beliefs you have about the future. I leave it to you to think this through thoroughly, at some time in the future. Even Demosthenes saw in his ancient time that, “No man can tell what the future may bring forth.”

Notice that the skeptic’s questions don’t just show that you can’t absolutely prove the reliability of your sources for beliefs about the past, present, and future. The point is much deeper. You can’t even provide one single, pure piece of evidence for this assumption you share with everyone else, and on which the credibility of all your other particular beliefs depends: The sources of our beliefs are sometimes reliable.

And this fact is certainly surprising and perplexing, if not deeply troubling. Where is your anchor to reality? What ties your belief-forming mechanisms to the way things really are? The skeptic has questions. And there seem to be no good answers. But, of course, as is often the case in philosophy and life, it gets worse before it gets better. Or, it becomes at least crazier and more interesting. To find out, look at the next section, which covers a whole different type of skeptical questioning, as we go from the frying pan into the fire.