30 More Fallacies

30-more-fallacies-coverI’m giving the PDF version of my  30 More Fallacies as a pre-Winter Holiday* gift to the readers of Talking Philosophy. I will leave it to your discretion as to whether you have been naughty or nice (and whether the book is a reward for being nice or retribution for being naughty).

As a shameless plug, this book is also available for the Amazon Kindle and the Barnes & Noble Nook for 99 cents at http://www.amazon.com/30-More-Fallacies-ebook/dp/B0051BZ8ZK or http://www.barnesandnoble.com/w/30-more-fallacies-michael-labossiere/1101987481.

For those in the UK, the Kindle book is available for .86 pounds at http://www.amazon.co.uk/s/ref=nb_sb_noss?url=search-alias%3Ddigital-text&field-keywords=30+more+fallacies&x=0&y=0

This book is a follow up to 42 Fallacies, which is also available for the Kindle  for 99 cents at http://www.amazon.com/42-Fallacies-ebook/dp/B004ASOS2O or .86 pounds at http://www.amazon.co.uk/42-Fallacies-ebook/dp/B004ASOS2O/ref=sr_1_1?ie=UTF8&qid=1321051637&sr=8-1

The Nook version is available at http://www.barnesandnoble.com/w/42-fallacies-michael-labossiere/1030759783.

*Perhaps Christmas

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  1. Thats very kind of you Mike. Thanks.

  2. Mike,
    Browsed ten or so pages. Nice little book.
    Whenever I try to learn the logic of argumentation I ultimatey give up. It’s not the logic I have trouble with but what seems to me the multitude of terms one must understand clearly to understand the different aspects of an argument. Your introductory exposition seemed reasonably rigorous to me, which really at this point ain‘t saying much. Lots of good examples.
    About examples: each example tells a tiny story and as such, I’m sure, you want it to be interesting. You can’t rely on animals to keep your readers engrossed forever. But if I were writing anything, especially in mathematics or logic, which required a lot of examples, I’d steer away from any hint of political preferences, unless I were writing the book for liberal democrats, otherwise it can be a turn off and almost certainly a distraction.

  3. Mike.

    Many thanks for the interesting book.
    I am not clear on this one, and would, if you have time, appreciate your comments.

    Example of a Strong Inductive Argument
    Premise 1: Most American cats are domestic house cats.
    Premise 2: Bill is an American cat.
    Conclusion: Bill is domestic house cat.

    An inductive argument claims that its premisses give only some degree of probability, but not certainty, to its conclusion. The relationship claimed between premisses and conclusion is much less strict and different in kind from from that of a deductive argument.
    The expression “Most American cats” would be true if it only referred to say, 51% of American cats, which would make the conclusion highly tentative.
    In these circumstances do you agree that the conclusion would be better expressed as “Bill is probably domestic house cat”?

  4. Don,
    I agreed with what you feel is a more reasonable conclusion but thought that Mike’s is standardly given. From Google, under strong inductive argument: “However, since, in most cases that we experience, the premise as stated would usually lead to the conclusion given, we are logical in calling this argument an instance of strong induction.”
    I wonder what the “strong” refers to?

  5. Re. Author: Gra
    Before this I had never heard of the expression Strong Induction. As a matter of interest I have collected Books on Logic for some years. A quick look through the older ones does not reveal the expression ‘Strong Induction’ I have not had time to look at the newer ones. I assume it is a fairly recent expression. Certainly Wikipedia defines it. I suppose it depends on the number confirming instances one has of say if p then q. 10000 confirming instances may indicate a strong probability that the next p will be a q. 10 confirming instances would I suppose be much weaker.
    The first premiss in Mike’s argument I found a bit worrying how would one know one had examined MOST American cats, this presumably includes a large number of Lynx, Puma, Ocelot, Jaguar. There are about 60,000,000 house cats in USA so they could well outnumber all other species. I suppose on those grounds one might say this is a strong argument. But it is still not a deductive argument and for that reason I think the conclusion I suggest, “Bill is probably domestic house cat”? may be better.

  6. Don,
    I definitely agree with you on “Bill is probably a domestic house cat.” Deciding whether Bill is a house cat or not isn’t very important, probably ever, but say we had:
    Premise 1: Most Americans are cured of disease X by using drug A.
    Premise 2: Don is an American.
    Conclusion: Don will be cured of X if he takes A.
    Say again the ratio is 51 to 49 with the 49% having dire side effects as well as not being cured. Doesn’t give you much confidence in strong induction.

  7. Re Author:Gra.
    Alfred North Whitehead stated that, “ This process of reasoning from the sample to the whole species is Induction. The theory of induction is the despair of philosophy –and yet all our activities are based on it.”
    The process of Induction does form a large part of scientific method. A scientist would I think, find it almost impossible to get a paper published in which his findings were such that his conclusion was only 51% likely.
    Actually I think Mike would argue that his example far outstrips that figure and in fact his conclusion is probably correct. My argument is essentially, that he should insert the word ‘Probably’ (or maybe even, ‘Highly Probable’) in his conclusion as all inductive reasoning is based on just that, even where it seems to verge on certainty, as does our belief, based on induction, that the sun will rise tomorrow. I suppose that is a very strong inductive conclusion when you consider the number of times humans have witnessed the phenomenon.
    I think the example you have given may be an example of weak induction as opposed to strong. However as I have already said, both theses terms in relation to Induction, are new to me.

  8. Hey Don,
    I have a once in a lifetime deal for you. Why don’t we read Mike’s fallacies “together,” via email? I have a math background so shouldn’t be a complete loss if we partner up.
    Ralph rrsvvc@yahoo.com

  9. Don,

    Good points-they illustrate the potential perils of informal inductive reasoning. As you note, “most” can be taken to mean “more than half.” As you note, if only 51% of American cats are domestic house cats, then the argument would be rather weak. However, “most” is most often used in informal language to mean “a good bit more than half” or even “a significant majority” and this would make the argument strong. For example, if I were to say “I got most of the answers right on the test” you’d probably take me as meaning that I did better than just 51%.

    Because of this sort of problem, more formal inductive arguments of this sort (which are often called statistical syllogisms) put in actual numbers. So, for example, this would be a strong argument:
    P1: 83% of American cats are domestic house cats.
    P2: Bill is an American cat.
    C: Bill is a domestic house cat.

    In regards to the second point-yes, you are quite right. When people are being more formal about it, they should be careful to express their confidence (or lack thereof) in the statement of the conclusion by qualifying it appropriately.

    Naturally, folks tend to use the informal language in most cases.

  10. Gra,

    I do have a tendency to include some political examples-mainly because so many fallacies are committed in the context of politics. However, I did endeavor to avoid taking the left or the right to task in particular. I do admit that I did not count my examples to see if they were completely balanced. However, if anyone takes issue with the balance or content of the examples, I am happy to add more relevant and accurate examples to be both fair and balanced. In fact, I encourage people to post their own examples here.

  11. Gra,

    In the case of the disease, you would want a more formal induction-that is, one that replaces informal terms like “most” with actual numbers. In such a case, a 51% chance would result in a weak inductive argument. Another “problem” with inductive arguments is that there is generally not an exact boundary between weak and strong (although in statistics they do have standards for generalizations, ect.).

  12. Gra,

    The term “strong” is used to refer to how well (logically) the premises (if assumed to be true) support the conclusion. Roughly put, if the evidence offered (if it were true) would give you good grounds to be confident in the conclusion, then the argument would be strong. If not, it would be weak. A strong inductive argument with all true premises is often called “cogent.”

    Deductive arguments are valid or invalid (and also sound or unsound). This is “rating” of how well the premises support the conclusion (on the assumption the premises are true).

    I’ve been familiar with the term “strong” since my Freshman logic class back in 1984-so it has been around at least that long. 🙂

  13. Mike,
    Is there a “jumping to conclusions” fallacy? My political preference comment probably would be a good example.
    I came across another way of characterizing strong induction argument “an argument where it is not probable that its conclusion is false given that its premises are true”. I can see why Alfred North Whitehead stated that, “ The theory of induction is the despair of philosophy.” (See Don Bird’s comment, above.)

  14. Mike,
    I just realized that jumping to conclusions is what induction is all about.

  15. Mike,
    In the first page of your introduction: “If a deductive argument’s premises properly support . . . then the argument is valid. In technical terms, a valid deductive argument is such that if all premises are true . . .”
    Consider the following deductive argument:
    1. NYC has 5 boroughs.
    2. The Bronx is a Borough of NYC.
    Conclusion. I was born in the Bronx.
    By the technical terms of describing a valid deductive argument, this would be valid. But it doesn’t seem to be using the nontechnical description.
    I can see that I’m probably reading your statements not as you meant them. Did you mean for the “premises properly supporting the conclusion” to hold in the second sentence? If so, it’s not clear as written.
    Mike, any chance of discussing your book off the blog? If so,

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