Internet Goosing the Antithesis

Thursday, January 26, 2006

"You can't prove a negative !"

"You can't prove a negative !". This is one of the most absurd and obtuse beliefs anyone could have about epistemology. Basic rationality, and basic science, goes completely against it. And yet throngs of skeptics and believers alike (two groups of people I have no love for) spout this nonsense as if it was a fait accompli.

Let me first state the obvious. Science progresses by proving negatives. More specifically, it is by constructing possible models of a phenomena (a hypothesis), and then testing them (falsification), that we advance and build on the knowledge that we already have. By doing so, we prove many negatives along the way. We came to the conclusion that oxygen is the necessary gas in burning because we were first able to disprove the existence of phlogiston, which was the reigning scientific position at the time. More exactly, we now say that oxygen is a better explanation of burning than phlogiston, because the first fits all the facts while the second does not.

In fact, it is considerably easier to prove a negative (or even a universal negative) then it is to prove a positive. To prove a positive requires extensive testing and decades or centuries of confirmation. To prove a negative can take only one experiment ! As soon as a piece of data disproves the proposition, the negative is proven. Of course, if a model fits most facts perfectly and only disagrees with a few facts, it may very well be that the model does not need to be trashed, but rather modified.

The idea of proving negatives by testing is also part of a basic epistemic principle, Occam's Razor. If you have two models explaining the same data, and one is simpler than the other, then the simpler one is true and the complex one is false.

The "can't prove a negative" contingent then tries to rationalize that away by saying that Occam's Razor is just a preference or a probability. This is nonsense. Occam's Razor is nothing more than a restatement of the fundamental rational standard that "to assert something you must have objective evidence". If you have two competing models, and one is more complex than another, then the complex ones has additional entities or processes which have no evidence to validate their existence.

Going over this, the "can't prove a negative" crowd will then try to remove the object of inquiry outside of human cognition. Here is a famous example, Carl Sagan's "The Dragon In My Garage" :

"A fire-breathing dragon lives in my garage"

Suppose (I'm following a group therapy approach by the psychologist Richard Franklin) I seriously make such an assertion to you. Surely you'd want to check it out, see for yourself. There have been innumerable stories of dragons over the centuries, but no real evidence. What an opportunity!

"Show me," you say. I lead you to my garage. You look inside and see a ladder, empty paint cans, an old tricycle -- but no dragon.

"Where's the dragon?" you ask.

"Oh, she's right here," I reply, waving vaguely. "I neglected to mention that she's an invisible dragon."

You propose spreading flour on the floor of the garage to capture the dragon's footprints.

"Good idea," I say, "but this dragon floats in the air."

Then you'll use an infrared sensor to detect the invisible fire.

"Good idea, but the invisible fire is also heatless."

You'll spray-paint the dragon and make her visible.

"Good idea, but she's an incorporeal dragon and the paint won't stick." And so on. I counter every physical test you propose with a special explanation of why it won't work.

Now, what's the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all? If there's no way to disprove my contention, no conceivable experiment that would count against it, what does it mean to say that my dragon exists? Your inability to invalidate my hypothesis is not at all the same thing as proving it true. Claims that cannot be tested, assertions immune to disproof are veridically worthless...

If a belief cannot be falsified in any way whatsoever, then what does it mean ? The meaning of a concept is a set of properties that we can use to differentiate between instance of that concept and other objects around us. The meaning of a table can be subsumed into these properties : furniture - flat horizontal surface - one or more vertical legs - used to eat on or support objects. I can use this meaning to look at different things and figure out whether they are tables or not.

Now if you present me a concept that is not falsifiable, such as the dragon, we cannot possibly extract any meaning from that concept. There is absolutely no way to distinguish it from anythnig else - in fact, that is its selling point ! So such talk is, like religious talk, complete gibberish that can only have significance for the individual within a specific inter-subjective context.

The case of the word "god" is very similar. "Weak atheists", agnostics and believers all try to push "god" into unfalsifiability. But as I said before, that makes it meaningless, and therefore disproven because of its inability to fulfill the smallest burden of proof. The other problem is that this unfalsifiability is plainly false, as the Problem of Evil and other atheistic arguments prove.

So where does this silly belief "you can't prove a negative" come from ? I think part of it is the impulse from American skeptics and atheists, who live in a country hostile to rationality and don't want to make more enemies than they need to, are very quick in deflecting possible conflict with believers. So they will adopt such a "tolerent" attitude even though it is completely irrational and destroys their own epistemology. And I doubt it actually helps much, since believers will always be convinced that we think they are wrong... and who can blame them ? They are obviously right in thinking that we do.

Post a Comment


At 1/26/2006 12:55 AM, Blogger BlackSun declaimed...

Good point, Francois!

At 1/26/2006 10:02 AM, Blogger Zachary Moore declaimed...

I'd like to request a part 2 to this- how to handle those Christians who argue that "God did it" is the simpler way to explain the data. Perhaps an illustration of the complexity and contradiction of the God-concept.

At 1/26/2006 2:43 PM, Blogger Francois Tremblay declaimed...


At 1/26/2006 4:20 PM, Blogger streetapologist declaimed...

I am curious, you are basically discussing falsification however Flew says in his interview with Gary Habermas that he went where the "evidence" led. Care to comment?

At 1/26/2006 4:33 PM, Blogger Zachary Moore declaimed...


Flew only references two evidences in that interview. The first is Near Death Experiences, although he says that, "Where any such
near death experiences become relevant to the question of a future life is when and only when
they appear to show 'the occurrence of human consciousness independent of any occurrences in
the human brain.'" There's no citation of any medical or scientific evidence to bolster that claim.

The only other type of evidence he references (probably because of the interviewer) is the evidence for the Resurrection. But even there he says that, unfortunately "what we do not have is
evidence from anyone who was in Jerusalem at the time, who witnessed one of the allegedly
miraculous events, and recorded his or her testimony immediately after the occurrence of that allegedly miraculous event."

So perhaps this isn't the best source to present evidences for belief.

At 1/26/2006 4:43 PM, Blogger streetapologist declaimed...

I am not citing Flew as a source of evidence, per se. I was just curious what your (you and the others) take is on Flew's consideration of the "evidences" that caused him to reconsider his dogmatic commitment to atheism.

At 1/26/2006 4:47 PM, Blogger streetapologist declaimed...

This comment has been removed by a blog administrator.

At 1/26/2006 5:24 PM, Blogger Zachary Moore declaimed...

I would say that Flew's evidence (at least that which is mentioned in that interview) is very poor, as he seems to acknowledge.

Specifically as to the evidence for the Resurrection, I find it highly suspect that there are no independent corroborations by contemporary historians of the Christological events reported in the Gospels, especially the resurrection of the saints in Matthew 27:52,53.

At 1/28/2006 3:12 PM, Blogger Brent declaimed...

This comment has been removed by a blog administrator.

At 2/06/2006 2:29 AM, Blogger Francois Tremblay declaimed...

I didn't express my point quite accurately. My point was not that OR is not probabilistic per se (as after all knowledge is probabilistic), but rather that it is not relatively MORE probabilistic than, say, logical deduction.

At 3/04/2006 1:44 AM, Blogger Ian2400 declaimed...

I like how none of the theists can come up with a good argument against this...

At 8/10/2006 11:44 PM, Blogger ~~~ Natasha !!! declaimed...

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At 8/26/2006 6:33 AM, Blogger fish declaimed...

Many people know the importance of self confidence and try to boost their own by using many different personal development models. Self confidence to most people is the ability to feel at ease in most situations but low self confidence in many areas may be due to a lack of self esteem. Low self esteem takes a more subtle form that low self confidence. So if you are tired of feeling not good enough, afraid of moving towards your desires and goals, feel that no matter what you do it is just never good enough, then your self esteem could do with a boost.

Every day we make decisions based on our level of self-esteem. We also exhibit that level of self esteem to those around us through our behaviour. 90% of all communication is non-verbal - it is not what you say but ho you say it that matters! Your body language, tonality and facial gestures can all tell a completely different story to your words. It is our behaviour which influences others and people react to us by reading our non-verbal communications. Have you ever met someone you just didn't like although on the surface they seemed polite and courteous, or you met someone who seemed to speak confidently yet you knew they were really frightened underneath and just displaying bravado?

Parental and peer influences play a major part in moulding our level of self-esteem when we are children and in our early years of adolescence. The opinions of the people closest to us and how they reacted to us as individuals or part of the group was a dominant factor in the processes involved in forming our self esteem.

As adults we tend to perpetuate these beliefs about ourselves and in the vast majority of cases they are ridiculously erroneous. It is time to re-evaluate our opinion of ourselves and come to some new conclusions about these old belief patterns.

Ask yourself some serious question:
Is your long-held view about yourself accurate? Do we respect the sources from which we derived these beliefs? Most of the negative feedback we bought into as we were growing up actually came from people we have little or no respect for and as adults we would probably laugh their comments away! Yet the damage to your self esteem was done when you were very young and you still carry it with you to this day.

Is it possible that even those people you respected, who influenced your self-worth, were wrong? Perhaps they had low self esteem also.

As adults we have the opportunity to reshape our self-esteem. Try to judge accurately the feedback you receive from people you respect. This process will allow you to deepen your understanding of yourself and expand your self-image. It will also show you were you actually need to change things about yourself and were you don't. Many people are striving to better themselves in areas where they are just fine or actually excelling and it is only because they have an inaccurate picture of themselves in their minds due to low self esteem!

Setting small goals and achieving them will greatly boost your self-esteem. Identify your real weakness and strengths and begin a training program to better your inter-personal or professional skills. This will support you in your future big life goals and boost your self-esteem and self confidence to high levels you didn't existed!

Learn to recognise what makes you feel good about yourself and do more of it. Everyone has certain things that they do which makes them feel worthwhile but people with low self esteem tend to belittle these feelings or ignore them.

Take inventory of all the things that you have already accomplished in your life no matter how small they may seem. Recognise that you have made achievements in your life and remember all the positive things that you have done for yourself and others. Take a note of your failures and don't make excuses like "I'm just not good enough" or "I just knew that would happen to me", analyse the situation and prepare yourself better for the next time. If someone else created success, regardless of the obstacles, then you are capable of doing the same! Remember everyone has different strengths and weakness so do not judge your own performance against that of another just use them as inspiration and know that what one human being has achieved so can another!

Surround yourself with people who respect you and want what is best for you - people who are honest about your strengths and will help you work through your weakness. Give the same level of support to them!

Avoid people who continually undermine you or make you feel small. These people are just displaying very low self esteem. As your own self esteem grows you will find that you are no longer intimidated by another's self confidence or success and you can actually be joyful for them! Do things you love to do and that make you happy. A truly happy person never has low self esteem they are too busy enjoying life! By getting busy living your life with passion and joy you will not be able to be self-consciousness.

If you find yourself feeling self-conscious in any situation focus on the fact that others can tell and many of them will be feeling the same. Be honest. People respond to someone better if they openly say "To tell you the truth I'm a bit nervous" rather than displaying bravo or fake confidence that they can see right through. Their reactions to you, will show your mind at a deep level, that there was actually nothing to be frightened of and everything is great. If someone reacts to this negatively they are just displaying low self esteem and very quickly you will find others noticing this! Really listen to people when they talk to you instead of running through all the negative things that could happen in your head or focusing on your lack of confidence. People respond to someone who is truly with them in the moment..

Breath deeply and slow down. Don't rush to do things.

Stop the negative talk! 'I'm no good at that' or "I couldn't possibly do that" are affirmations that support your lack of self esteem. Instead say "I have never done that before but I am willing to try" or "how best can I do that?". Which leads us to the last point - the quality of the questions you ask yourself s very important.
When you ask a question it almost always has a preposition in it. For example, "How did I mess that up?" presumes that something was messed up, a better way of phrasing the question would be "what way can I fix this quickly?", as this presumes you can and will fix it. Or "How am I ever going to reach my goal?" could be rephrased as "what way will lead me to my goal quicker" presumes that you are going to reach your goal! Get the picture? Change the quality of your questions and your results will change!

Practise these techniques and watch your self esteem rise day by day. personal development

At 6/18/2007 4:46 PM, Blogger F. Bailey declaimed...

Carl Sagans "Dragon in the Garage" is the hight of foolishness. To assert the existance of something foolish in order to prove the non-existance of something else is tantamount to saying because Santa Clause does not exist neither do your parents. Just because science is bent on explaining away God through imperical devices does not negate the existance of socialogical, psychological, testamonial, natural, and logical evidences of His existance. Your correction of your OR argument is problematic in that you assume that logic is the only way to prove God. Logic does and will continue to prove God however the testimonial arguments from every culture and continent throughout history would certainly be stronger and more simple. I suppose that you would explain away all of the complexities of the human body and the cosmos as well as nature, as being more simply happenstance rather than intelligent design. It seems to me that you would have an easier time proving that you have a dragon in your garage. Especially since the dead Carl Sagan has given you the verbage for such an argument.

At 10/22/2007 4:03 PM, Blogger John declaimed...

F. Bailey says, "I suppose that you would explain away all of the complexities of the human body and the cosmos as well as nature, as being more simply happenstance."

No, I wouldn't. The complexities of nature are the result of evolution by natural selection, which is absolutely not random happenstance. Actually, evolution is un-intelligent design-- design which is guided by natural forces and dynamics, namely natural selection, or survival of the fittest. It's so easy to understand, and yet fundamentalists keep refusing to understand. Over time, small genetic mutations cause changes in physical traits of individuals. Harmful changes cause early death or the inability to find a mate. Other changes promote survival and mate attraction, and these changes get passed on to offspring and further propagated. This is evolution by natural selection.

Different species arise when a group of individuals from one species become geographically separated from the original population. Over millions of years, numerous small genetic changes accumulate in the separated population, until the genetic makeup of the two populations are so different that they can no longer have offspring together.

The massive evidence for evolution comes from many branches of science. Evolution has had an overwhelming consensus among all types of scientists, including millions of scientists who are Christians, for well over a hundred years, and no contrary evidence has ever appeared. There is no massive conspiracy to promote evolution. That's because evolution is true, and it doesn't need a conspiracy.

Evolution is supported by evidence. God isn't supported by evidence. No more, anyway, than is Sagan's dragon in the garage.

At 5/09/2008 1:38 PM, Blogger bobcarp declaimed...

Can one prove they've NEVER killed someone? Asking one to prove a negative is the height of foolishness and only a tool used by the frustrated who cannot prove what they themselves believe is in fact true. Dr. Sagan illustrates this foolishness expertly in his "Dragon in Garage" scenario. One can no more prove there is no dragon then one can prove there is no Jesus god or Hindu god or Islam god. One cannot prove the bible or Hindu writings or Koran IS NOT just the rantings of mortal man. Can a Christian prove an angel “DID NOT” appear before Mohammad and dictate the Koran? The burden for any rationally thinking, educated person should always be on the positive. Placing the burden on the negative lends to no academia to the discussion and is used only as a tool to reinforce ones already present personal beliefs.

At 7/12/2008 10:01 PM, Blogger Samuel Saltman declaimed...

I came upon this blog because I happened to think to myself today: "Wait! Isn't falsification -the bedrock of scientific inquiry -the same as 'trying to prove a negative'?" I'm not a scientist, nor am I religious; I consider myself a "natural philosopher," who follows Spinoza's school of thought that "God" is the totality of existence. I read another blog - - which argues that science is all about proving the negative, i.e. falsification. Now I'm sure I've misunderstood a ton of what I've read tonight, so forgive my being a neophyte. But, is this post basically saying the same thing, i.e. proving a negative is not only possible, but is also one and the same of falsification?

At 7/30/2008 11:07 PM, Blogger Martin declaimed...

After hearing the phrase in question over and over from a number of professors, and wondering how the mainstay of positivism can exist alongside its opposite, I googled "prove a negative" and falsify, and landed here. I think you're completely right, but "a phenomena" is a linguistic atrocity. Please fix that.

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