A Discussion and an Introduction

[Matthew]

For those who really do not want to plow through a book on philosophy but have an interest to understand a little but more about logic I would like to start a thread using "With Good Reason" to introduce and discuss the matter. I am of course a novice but find the subject very interesting.

Regards,
Matt.

[Tyler]

Well, the book sounds interesting, and I might read it some time. I've picked up on informal logical fallacies in different books I've read, but I haven't seen a single book dedicated to them.

I've forgotten a lot of the formal logic I've read, but I do remember some of the formal fallacies. Some of them are significant ones.

The fallacy I come across most often is begging the question, but it's also really hard to detect. Even so, it's depressingly common.

In general, my own experience with reasoning is that, 90% of the time, the mistake someone makes is actually somewhere in the premises.

The greatest use I've found from knowing informal fallacies is that, once you learn them, you'll never watch the news or read a paper the same way. You really start to see the world in a different and cleaner light.

[Matthew]

I agree Tyler. But one of the advantages of Engel's book is that it presents the fallacies of logic not merely as a tool for assessing philosophical arguments but as guides to clearer thinking overall. The examples he uses relate to media and to our exposure to any a number of sources of enticement. It seems to address precisely the value you have found within logic.

Of course, in an argument, true or falsity is dependant upon the factual nature of the premises. Whether an argument is valid is based upon whether the conclusions follows from the premises with necessity if a deductive argument or with a high degree of probability if an inductive argument. Finally, an argument is sound if the premises are true and the conclusion follows from the premises. It is interesting that truth, validity and soundness have more to do with form than with content.

One can posit quite a few things and still end up in error on the basis of logical fallacy though. I recently was presented with an argument that went something like:

Major Premise: All texts containing verifiable information are true.
Minor Premise: The Bible contains verifiable information.
Conclusion: The Bible is true.

This argument appears to me to be true, valid, and sound. The premises are true, the conclusion follows with necessity from the premises and therefore the argument overall is sound. However, it is also logically fallacious (and in more than one regard). Can you identify how (we don't need to use the specific latin nomencalture but I am sure we can still identify the problems)?

Now note that I am not arguing for or against the "truth" of the Bible but rather that the argument itself is fallacious.

Regards,
Matt.

[Matthew]

A bit of an addendum. As I understood it begging the question relates to assuming the conclusion within the premises. Would that not be fairly easy to detect? Why have you had difficulty identifying it? Do you think its a matter of experience?

Regards,
Matt.