10 Does Skepticism Make Sense?

My objective is to address the conceptions that most of you have about the philosophical problems that involve skepticism.  It is not my goal to convince you that skeptics are right or to increase your own skepticism.  I do want to convince you that philosophical skeptics are not fools or mere extremists, and that the issues posed by skepticism are important – not just to philosophers, but to anyone who thinks beyond convention.  So, I am taking a position here, mostly for the purpose of demonstrating what is worth understanding about skepticism.  Of course, I do not expect you to agree with me.  You can refute the skeptics all you like.  Let’s just do so with a clearer understanding of the position.  I am not intending to be harsh on anyone here.  I am taking up a defense of the significance of skepticism to make a point

For the most part, the consensus among you is that skepticism does not make sense and is too extreme. I have addressed before the question as to whether being “extreme” makes a theory false.  I see that many of you continue to use that principle – i.e. extreme claims cannot be true.  I’d sure like to have that explained to me.  Especially since some of the folks who regard skepticism as extreme, go on to assert some remarkably absolute (extreme?) positions.  Again, I am not attacking your views or statements – but if we don’t get clear on this point about skepticism, then not much of the rest of the term will make sense.

What Is Knowledge?

The most important issue that skepticism brings to philosophy is the problem of clearly understanding what ‘knowledge’ is.  This problem affects science, politics, ethics, and any area of life in which certainty matters.  There are differences between knowing and guessing.  There are differences between knowing and believing.  These differences can be critical.  For example, the US is still fighting a war in which our leaders claimed to know with certainty that Iraq possessed weapons of mass destruction.  They said that the matter was certain beyond doubt.  They turned out to be 100% incorrect. Please understand, I am not making a political point here.  I am not discussing whether the war was right or wrong.  I am saying that the war on Iraq has had significant consequences.  And that the justification for starting the war was on the basis of certain knowledge claims; claims that turned out to be false.  Therefore, the question as to what counts as knowledge – how and when we can rightly claim to have knowledge – has real-world consequences.  It is not a purposeless and trivial concern of academics with too much time on their hands.

I hope that we can agree with this much philosophically – when a claim that someone makes turns out to be false (inaccurate, factually incorrect, mistaken, erroneous), then we can no longer say that the person had certain knowledge.  We can only have knowledge of that which is true.

Example – during the invasion of Iraq an interviewer asked Secretary of Defense Rumsfeld why the military had not yet found WMDs (nuclear, chemical, and biological weapons) in Iraq.  Rumsfeld answered that he not only knew that Iraq had these weapons, but he knew exactly where they were.

Since the weapons were not where he said they were, and in fact were never there at all, we can only say that Rumsfeld did not have the knowledge that he claimed.  Perhaps he thought that he knew, but thinking that you know (i.e. believing) is not the same as knowing, especially when you turn out to be mistaken.

Here is what I think the example of the war on Iraq shows us.  When we are certain that we know something, we stop looking for evidence and verification.  Shortly after 9-11-2001, US leaders expressed total certainty that they knew that Iraq had WMDs.[2]  Consequently, they had no interest in further investigation and evidence.  When contrary evidence was raised, they dismissed it immediately. When you are absolutely certain that you know something, you do not feel any need more evidence or even discussion; the case is closed.  History is full of instances of people whose certainty turns out to be mistaken.  In many of these cases, if they had held open some possibility of doubt, for instances by applying stronger standards of evidence, the situations may have turned out quite differently.

My main point: it is possible for a person to think that they know something when they actually do not.  Knowledge is not purely subjective.

Perception Is Knowledge/reality

Some folks reject skepticism because they favor an epistemological theory about the relations of knowledge to the senses.  This theory is summarized as; “Knowledge is perception.”  This theory has a long history, starting with Protagoras (ca. 490– 420 BC) and in continual use up to the present.  There are different versions of this theory, some more sophisticated than others (you can find a brief account of Protagoras’ theory in the Portraits section of the course site).

I suspect that what many people mean by “knowledge is perception” is that each of us has experiences and of those experiences, we are the best judge.  So when I have an experience, I have direct access to (knowledge of) that phenomena.  For example, I know when I have a headache because I am the one having it; I know what I believe, because it is my belief.  Even if I am having a dream or hallucination, the experiences are still real ones, and so I know what I am experiencing (because the experiences are mine).  I’ll call this the theory of subjective reality.

Another version of this view is presented by the claim “perception is reality.”  Again, this claim can be interpreted in several ways, with historical examples for the different interpretations.  George Berkeley (1685-1753) provided the strongest interpretation and defense of this idea (you can find a brief account of Berkeley’s theory in the Portraits section of the course site).  His theory of Idealism is a careful analysis and systematic argument. His famous aphorism summarizing Idealism is: Esse est percipi; Latin for “To be is to be perceived.”  It is interesting to note how some contemporary theories in physics continue to intersect with Idealism (i.e. with respect to the role of observation).

I think that for many people, the claim “perception is reality” is another way of expressing the theory of subjective reality (explained above).  It is a way of affirming that ‘my perceptions are real.’  Indeed they are.  A perception is just as real and factual as anything else in existence, even if it only lasts a short time.  It would be infuriating for someone to tell you that your perceptions and feelings are not genuine. Since you are the one having those experiences, you are the one to judge what they are and that they are.  In this sense, saying that your perceptions are real is equivalent to saying that you are the one who knows what and that they are.  The reality perception and knowledge of that reality are the same idea.

Is Perception All That There Is?

A difficulty arises when some people use the theory of subjective reality as a general theory of all knowledge and all reality.  It seems to me that when some people say “knowledge is perception” or “perception is reality” they are implying that the ONLY reality/knowledge is perception.  If that is what someone is saying, then we need a very careful account of that theory.

I am not ruling it out, mind you.  Protagoras and Berkeley are 2000 years apart and both seriously supported related theories.  Solipsism is another related theory of importance.

What strikes me is how often the generalized version of the theory of subjective reality is conjoined with a complaint that skepticism is “too extreme.”  It seems to me that the assertions “my perceptions are the only reality” or “all knowledge is perceived by me” are more extreme than any skeptical theories that I know of (given that ‘extreme’ means something like ‘total’ or ‘absolute’; and recall that I don’t see any prima facie reason why ‘extreme’ theories are less likely true than ‘moderate’ alternatives).

The issue comes down to this: does there exist anything which is not perceived by you?

If you answer; “No. The only things that exist and all knowledge of them are in my perception (or consciousness).”  That is not an impossible view to hold (e.g. Solipsism or Subjectivism), though it will take some pretty careful analysis and reasoning to maintain it effectively.

If you answer; “Yes.  My perceptions are real, but they are not the only things that are real.  Other people’s perceptions are real, even though I don’t perceive them, and there are things in the universe that I don’t have any clue about.  Just because I don’t perceive something does not mean that it does not exist.”  If this is closer to your view, then you have some in common with the metaphysical view called ‘Realism’ or ‘Objectivism’ (look them up).

Now, some folks argue that none of this makes any difference, which is why “reality is perception” is a completely adequate answer to the problems of epistemology.  You may recognize this position when people say something like; “What difference does it make whether this is a dream or not.  I perceive it and it is real to me.  That’s all that matters.  Perception is reality.”  There are many variations.  The common factor in this line of thought seems to be that if it makes no difference to me (because I perceive it to be so) then there is no relevant difference in reality.  Thus the philosophers who have based arguments on such differences can be dismissed as irrelevant.

I have been arguing all along that these theories are different and that there are significantly distinct practical implications that follow from them.  Let’s take a fairly simple case and see if we can find any differences among the conditions of perception.

Case 1: While in bed and asleep you dream that you won the lottery; a big one.  It is a very vivid dream and very enjoyable.

Case 2: While at work and wide awake you check the lottery numbers and find out that you won the big prize.  Happy day.

Question: What is the difference (if any) between these two cases?

Based on what some folks have argued with respect to perception and reality, I’d expect them to say that there are no important differences.  In both cases you perceived that you won the lottery. Perception is reality, so both cases are equally real.

I suspect at this point that most people will say; “No, I’m not claiming that there are not differences between dreams and awake perceptions.  After all, dreams take place entirely in your mind.  Waking perceptions – at least true ones – take place both in the mind and in the world outside of the mind.  I’m just saying that what takes place in the mind is real in its own right, not that all of reality takes place in my mind.”

At this point, if you continue to maintain that “reality is perception” meaning that the only reality is what takes place in your mind, then I’ll not try at all to refute you.  You have a very interesting theory with important historical precedents.  I’m interested now to know what your reasoning is and to learn more about these ideas. I urge you to not concern yourself with people who dismiss your view as ‘extreme.’ It is interesting to note that this view is very much connected to the theories of some skeptics who doubt the existence of an external world at all.

On the other hand, if your view includes the possibility of objects existing outside of your mind and even separate from your perception, then you are closer to a realist or objectivist view.  After all, it is possible that a person could win the lottery even though they never perceived that they did so; such as if they forgot that they had bought a ticket and never checked.  Winning a lottery for real involves facts that happen in the world outside of the mind: what philosophers call ‘the external world.’

My main points: The claims “Perception is reality” and “knowledge is perception” are not as simple as they may seem.  A bit of analysis shows that most people do not accept the implications of these claims taken as general theories.  Most people intuitively accept the idea of an external world that exists independently of our minds and perceptions.

Knowledge of the External World

If you accept the possibility of a world that exists independent of your mind and perceptions, then the question must arise: what is the relation between the internal world (mind dependent) and the external world (mind independent)?  There are many ways in which the question about this relation leads to philosophical problems.

The problem appearance and reality: We might suppose that the relation between the internal and external world is direct and simple.  That is, we perceive the objects in the external world exactly as they are.  Information comes from objects into our senses which is processed into perception.  So, the objects of the external world are exactly as they seem.  But even though we commonly behave as though the external world fits our perceptions, we all know that appearances can be different from reality.  Sometimes things appear to be very close when they are far away.  The way things look or taste can change over time.  There are many ways in which the way things appear can vary depending on the conditions.  So, is it the objects that are changing with our perceptions following with accuracy or is it merely our perceptions that change?  I think that people normally understand that our perceptions are not strictly passive.  That perception is variable in ways that the objects of perception need not be.  If that is so, then appearance (perception) and reality (external world) are not perfectly matched.  Indeed, they may be quite far apart.  It is possible that our perceptions have more to do with the conditions of the human mind than with the properties of external objects.

The problem of error: If we never made any mistakes or misjudged the facts, then skepticism would have a hard time getting started.  In the perfect world, our perception of reality and the objects of reality would be perfectly matched.  Plainly this is not the case.  Misperception, misjudgment, misinterpretation, and error of all sorts are basic to the human condition.  This could not be so if our perceptions accurately matched the external world.  This is the starting point for the most fundamental philosophical skepticism.  If a significant portion of our perceptions (and conceptions) are not accurate matches to the external world, then the possibility of human knowledge is largely in doubt.  Moreover, if we have no reliable way to tell which beliefs and perceptions are accurate, then knowledge is very much in doubt.

The problem of perspectives: I am not the only perceiver in existence (or else a radical Solipsism is correct).  If there are other minds with their own perceptions, then everyone should perceive everything in agreement – supposing, that is, that our perception perfectly matches the external world.  Well, one thing for sure is that few people see things all alike.  Our perceptions of the world – of the very same objects – can vary radically from one another.  How is this possible?

Two possible explanations are:

  1. There are as many external worlds as there are perceives.  Each of them accurately perceives their own world that is independent of their mind.  Each external world is different from the others to some extent.
  1. Perception is variable according to individual conditions.  A color blind person perceives the world differently than a full-color perceiving person.  But that is because the information from the objects in the world is processed differently by the two people.  The difference is in them, not in the world that they both apprehend.  So then, which perspective is the correct one?  Well, no perspective is because the external world is that which exists independent of particular perspectives.  Yet, human beings necessarily perceive the world from a perspective.  Therefore, our perception of the world must be qualitatively different from the external world.  How then, can we ever know what the external world is like independent of any perspective?

There are many roads over many centuries to the skeptic’s conclusions.  I hope that my brief excursion has shown you ways in which the skeptic’s reasoning is not ridiculous or irrelevant as some of you may have thought.  In part, the philosophical skeptics’ issue comes down to this: can we say what the external world is like based on our internal experiences?

Here are two possible answers:

I see things exactly as they are.  What exists for me is just how it is.  I am never mistaken in this.  Everything I think and perceive is that which I know with certainty.  My perception is knowledge of reality, and that is all there is.

None of us see things exactly as they are.  Each person has their own perspective, just as a single person’s perspectives may change; none of these perspectives are accurately matched to the objects on the world.  Everything that I think and perceive is subject to error. In some cases we can detect the error, in others not.  My perception gives rise to beliefs, which may or may not accord with the truth. We can match some of our beliefs with reality to a high degree of probability, but never with 100% certainty.

One of these derives from the theory of subjective reality.  The other is an expression of a type of philosophical skepticism.  Perhaps neither suits your own thinking.  What reasons can you give for rejecting or modifying either of them?


[1]. Secretary Rumsfeld Remarks on ABC “This Week with George Stephanopoulos.”  March 30, 2003.  http://www.defenselink.mil/transcripts/transcript.aspx?transcriptid=2185

[2]. The Center for Public Integrity documents over 900 public statements from the Bush Administration about Iraq’s weapons of mass destruction and links with al Qaeda.  Those statements have all been shown to be false. Center for Public Integrity. 2008. The War Card.