I would be skeptical if I were you.
Radical skepticism dies before its first doubt. How can you be sure your stance to be skeptical can work? If you are truly skeptical, than you must be skeptical of your certainty to be skeptical? You can never form any opinion of how it really is, if you are set on doubting everything. Well, since I put the kibosh on skepticism need I write anything more? Yes—so let me just see what more I can say about skepticism.
Perhaps the most famous of skeptics is Rene Descartes. He determined to doubt everything. He found that there was one thing he could not doubt—himself. He state: “I think, therefore I am.” In latin in which he wrote it is: “cogito ergo sum.” As you will see I have problems with this statement.
My plan such as I have is to start with some famous skeptics (e.g. Sextus Emipiricus, Rene Descartes, and David Hume). Then, I will explore what is called radical skepticism and some of the problems with it. Finally, I will give a portrayal of modern skepticism.
The radical skeptics appeared with Pyrrho (c. 360 – c. 270 B.C.E.). He wrote nothing, but Sextus Empiricus, a later disciple, wrote his Outline of Pyrrhonism probably sometime in the second or third centuries Common Era (C.E). These skeptics believed if you made no decision in relation to any knowledge claim you would have peace of mind. How they dealt with sensory knowledge kind of fudges their complete skepticism. They (including other Greek followers of Socrates) excepted appearances or use a rough probability (nonmathematical), and so avoided falling in to ditches or burning themselves with fire.
After Sextus, the curtain on philosophy started to fall, and it was not until Rene Descartes that skepticism leapt to life. Descartes claim to fame was that he decide to doubt everything. But, this led him to claim that he could not doubt that he was thinking, hence his famous statement given above. He than began to think that god would not deceive us, so we could basically rely on his senses. How he made this leap is not clear to me. How did he eliminate his doubt of god’s existence? Some supposed logical argument, maybe. Anyway, I find this leap from his original certainty to be unacceptable. I also think there is reason to doubt his original certainty (see below).*
Before I go on to David Hume I will mention Pierre Bayle. It is not exactly sure where he stood, but he wrote a dictionary of sorts – Dictionnaire historique et critique (1697?). In English it is called Historical and Critical Dictionary. In it are various skeptical arguments. I am not sure what they are, but the historical scholar of skepticism, Richard H. Popkin, seems to think he is an important contributor to the history skepticism.
Hume is famous for two skeptical positions. First, he was no radical skeptic, at least not in his everyday life. He doubted that there was any real cause and effect in the world because there is no logical argument that can prove it. Induction in his opinion is incapable of proving it. For the next instance could be different. My argument against this position is that without cause and effect you would not observe the order in the universe. It is unbelievable that all this order happens to come about by the chance appearance of cause and effect. Another reason he was not a radical skeptic was nowhere that I know of does he say we cannot rely on the constant conjunctions of events to guide our actions.
Of course, this is not an absolute proof of cause and effect. For all we know the world could be caused according to Kalam philosophy. This is where god causes everything. He (after all this is an Islamic philosophy) causes both the cause and the effect, which gives us mere humans the appearance of cause and effect. God misleading his worshipers—just great. Of course, as a modern skeptic (more on this later) I reject this fanciful theory as having no evidence once so ever, despite its supposed logical reasoning, which I have not seen.
Hume’s other famous skeptical position is in ethics. You cannot derive “ought from is.” This is you cannot derive a reason for an action based on any fact about the world. Hume’s solution to this inability is that we are governed by moral feelings as to what is right or wrong to do. While, I am sympathetic to this position, I do not see this to exclude reasoning about these actions.* But, I believe there is a partial ability here to get from is to ought.¹ If you come to an ethical decision, you can determine if it is workable, or how to successfully carry it out using facts about the world.
Immanuel Kant had a skepticism of sorts. He thought that one could not know the world as it is in itself. But, he than went on to say lots of things about the world. And, he was definitely set as to how ethics was to be. So, I do not consider him much of a skeptic. This view of not knowing the world as it actually is I do not even consider to be valid, so it does not underwrite phenomenology (the world of appearances) as a philosophical method. Phenomenology is only acceptable as it is used in psychology.
The reason to reject this view is that we have direct access to the world via our senses. Light particles impinge on the retina giving sight (with a lot of brain processing); hearing is produce by sound waves hitting are inner ear anatomy (again with a lot of brain processing); taste and smell are based on chemical reactions on receptors in our noses and receptors on our tongues respectively (with somewhat less brain processing); and touch is provide by direct contact (the brain processes this too). While each person experiences will be different, there is enough intersubjectivity (everybody pretty much senses the same things in the same ways) to provide a reasonable amount of confidence that we have direct access via are senses to the world—there is no veil.
So lets us see how a radical skeptic could make his way in the world. His alarm goes off, and he wakes up. “Am I awake? I doubt it.” So, how does he (let us make him a he, since some men do not have a clue) know whether he is even awake or not. He swings his legs over the edge of his bed. But, he becomes paralyzed; he cannot put his feet on the floor because he doubts that the floor is solid. “Oh my gosh, what do I do now. Wait a minute, why should I doubt that the floor is not solid?” So, he puts his feet on the floor and manages to make his wishy-washy way into the kitchen.
“Wait, am I even walking? Whoah! I have been thinking, or maybe I haven’t. How can I even tell if I am thinking, if I am to doubt everything.” Okay Descartes, looks like your in trouble, maybe you can doubt that you are thinking. How can you tell for sure? Your just making a unwarranted claim. Where is your evidence. He says that he has a thought as exhibit A. But, can he introduce that into evidence, if he is to doubt everything? Even if we except this exhibit A, how can he prove that it is his thought? Maybe, it is somebody’s else, or god forbid, it could be god thinking his thoughts and not himself? But, you cannot really tell because your suppose to doubt everything. Descartes, just go back to sleep, and maybe, you will not have to think anymore.*
I mentioned the notion that it could always be god thinking Descartes’ thoughts above. This idea came about on combining his approach with Bishop Berkeley’s idealism, which argues against any physical world. Berkeley would have us believe that the permanence of our perceived world is god thinking it. So, if god can think the sensory world, cannot he think our thoughts as well? It certainly seems plausible to me. Descartes himself used god as a guarantor of the sensory world too, which would then lead him into the same error as Berkeley.
Berkeley, was said to be refuted by Samuel Johnson of dictionary fame. Johnson said, “I refute him thus,” and kicked a rock. The solidness of the rock was supposed be “rock solid” evidence for the physical world’s existence. Does the radical skeptic have to acccept Johnson’s argument? No, but neither can he deny it. By the way, Achilles could have refute Zeno’s argument that he would never catch the tortoise because he would have cover half the distance, but before he reach this point he would have to cover half that distance, and so on, so in effect could never even get started. All he would have had to do to refute Zeno was to take a step forward.
I mentioned above how some radical Greek skeptics chose to deal with sensory evidence. Even, Hume claimed somewhere that when he left his study (or, his ivory tower) he went about his business like anybody else. That is if he could know what anybody else was like. I cannot for the life of me remember where I read this, but I am pretty sure it was him. And, if not, it was somebody else.
But, is radical skepticism really a live option? Some have claimed that empirical evidence is theory laden. This is that our ability to determine facts is burdened by theory. For to believe the evidence of your eyes you need to know that this is a valid approach to gaining evidence. But then, the skeptic (the radical one) must doubt any theory on how we can rely on our sight to gain evidence. So, it seems that the options used to treat sensory evidence by the radical skeptic cannot be used to step out of his study door.
So, is skepticism then put to rest? At least I think the muddled headed radical skeptical kind. Here, I think one needs the concept of reasonable doubt, which leads me into the more healthy kind of skepticism of the modern skeptic. Is it reasonable to doubt that the objects in the room exist when I can navigate successfully through it, and if I do not, I can feel myself bump into something? Reasonable doubt is based on the idea that when you find it is reasonable to accept something, then you should be willing to act on it. And, since such actions work, doubt should be put to rest for all practicable purposes.
Modern skepticism contains the notion that you need to have evidence to accept a particular idea, theory, existence, etc. If you want me to belief in ghosts, produce one. After all, while this may be a difficult thing to do, it should not be impossible. If scientists can produce physical evidence for the Higgs boson, certainly it should be possible to produce a ghost if they exist. By the way, you should be able to produce god if he or she exists as well. The Higgs boson was called the god particle in the book of the same name by Leon M. Lederman. I think that this was an absolutely horrible name for the book, especially when in it, Lederman never claims anything like the existence of god, and of that I am certain.
Modern skepticism also demands coherent reasons for accepting ideas and objects. Some call this a logical argument, but I think this is a misnomer. To me, at least, logical reasoning is a technical endeavor, using such things like “if p, than q. p, therefore q.” or
“something cannot be both A and not-A” (the law of the excluded middle). Of course, in coherent reasoning these principles must be adhered to. Or, all most. There are some that reject the law of the exclude middle and go on to reason logically in the technical sense. The mathematical intuitionists are one species, and there are some proponents of it in quantum mechanics. Anyway, coherent reasoning just means that your reasoning is consistent. That it does not contradict itself. This is something truly follows from something else.
You put these two together, and what you have is basically modern skepticism. To accept something you need some kind of empirical evidence† and have some kind of noncontradictory reason to support it.
Sometimes modern skepticism is called scientific skepticism, not in the sense of not accepting science’s findings (these are called science skeptics), but in the sense that to accept a scientific theory (at least provisionally) one needs empirical evidence and coherent reasoning connecting the various evidences you are using in your argument. This is basically the approach of all scientists, hence the title scientific skepticism.
Some famous modern skeptics are T. H. Huxley (Darwin’s bulldog), Issac Asimov, Richard Dawkins, Martin Gardner, Harry Houdini, James Randi, and Carl Sagan. Huxley’s agnosticism sounds a lot like modern skepticism; Asimov was a co-founder of the Committee for the Scientific Investigation of Claims of the Paranormal (CSISOP); Dawkins is known for his fierce opposition to the belief in god’s existence, using evolution to dethrone creationism in the main; Gardner for years wrote the “Mathematical Recreations” column for Scientific American, although he was a theist, he was a critic of the paranormal and pseudoscience; Houdini and Randi of escape artist and magician fame respectively worked to debunk spiritualists and their ilk; and Sagan known for the phrase “billions and billions” wrote the excellent book – The Demon-Haunted World criticizing the same things as Gardner.
Well, I am off to doubt myself out of existence.*
¹ Sam Harris’ The Moral Landscape argues for the stronger position that morals can be based on scientific investigation.
* I have posted blurbs of these topics on my Possible Future Blog Posts page.
† I use “empirical” here because I do not believe there is any other type of evidence, as supernatural evidence stands on shaky ground, despite what the Bible says.