I wrote to the Foundation for Critical Thinking to ask their opinion about the value of teaching formal logic. I received the following response from Gerald Nosich, who is one of their senior fellows:

 

Hello Ron,

 

The Foundation for Critical Thinking does not have an explicit stance with respect to the value of formal logic. But I can tell you the conclusions I have come to with respect to the extent to which it fits with critical thinking, and I believe that my conclusions are in accord with those of Richard Paul and Linda Elder.

 

I studied a great deal of formal logic as a graduate student in philosophy, and I thought for many years that it was an essential part of good reasoning. I even wrote my first book based not on formal logic exactly, but on the closely related idea of deductive logic, with it's emphasis on validity and soundness.

But I no longer think formal logic has much value for critical thinking or for good reasoning generally. (I might make an exception for the logical foundation of mathematics.) Even putting aside the practice of using abstruse symbols, the concepts of validity and soundness virtually never apply to real arguments. They rely on absolute lack of ambiguity or vagueness--and natural language is almost universally both ambiguous and vague. And I once made a search for sound arguments: I examined several hundred. In every one I ever found, we are already convinced of the conclusion without needing the premises. (E.g., All mice are mammals; all mammals are quadrupeds; therefore, all mice are quadrupeds.) What a wanted to find was a deductive argument that was "interesting": meaning: one that led me deductively to a conclusion that I was not already fully convinced of.  (I'm not saying that there can't be any such arguments, only that I haven't found any. Maybe you can come up with one.)

Then there is the problem of the symbols and notations. At the beginning, I asked my students in advanced logic to take an editorial of any kind and restate it in symbolic notation. Not one could do it. Neither could I. (Maybe I could if I spent a full day on a single paragraph.) To test it out for yourself, take this letter and reformulate it in symbolic logic, with x's and y's and A's and B's  and &'s and v's, in any system of notation that you're familiar with.

If you look at the Foundation's list of intellectual standards, we list some main ones: clarity, accuracy, precision, relevance, depth, comprehensiveness, and so forth. Notice that formal logic gives no insight into any of them. In formal logic, we simply assume that the terms are clear. Accuracy, precision and relevance play no role at all (E.g., From "A & not-A" it follows logically, deductively that the sun goes around the earth). Depth and comprehensiveness are standards that logic does not even aspire to. As you point out, we do have the standard of logic among our standards, but "logical" there means what it means in English: it means that it makes sense, that one part of the argument does not conflict in a serious way with another part. It does not mean that anything does, or does not, follow according to the rules of formal logic or deduction.

This is too long a response to your brief inquiry. I hope I have not inundated you with far more than you were looking for.

Best regards,

Gerald