I am really interested in the topic of using logic to make conclusions and opinions that are solid. And then we have logical *fallacies* which are also interesting. I would like to learn them. I have a vague idea of what they are, but I don’t know what any of them are called or how it’s all structured.
Growing up, I was never taught it by school or by my parents (they reasoned using emotion instead of logic).
I was going to ask for good *books* on the topic, but there may be online resources that will help me learn a bit faster than a full-length book. Maybe video or audio, maybe some charts, etc.
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On online stuff, I usually visit the Ted Ed channel for logical puzzles.
Lots of resources online …look up “critical thinking.”
I bought some of these [‘critical thinking cards’](https://thethinkingshop.org/) for my kids this Christmas. I like keeping a deck of them around to check in on once in a while and remind myself of my cognitive biases.
This is a great question. I don’t have any specific recs, but I will say that taking a stats class in college changed how I looked at the world. It’s hard to make informed decisions based on data if, on a fundamental, mathematical level, you have no idea what the data means.
That organization run by Jonathan Haidt
ooh, i know this one! start with sagan’s “the demon-haunted world.” it’s a users’ manual for the human brain.
then review your logical fallacies and try to spot them in the wild, like a birdwatcher. it becomes a habit pretty quickly.
there are debate subs you can lurk on here, the people on them are pretty good at spotting fallacies and maintaining a logical skepticism.
There is a great YouTube channel, “Why Logic Pro Rules” that really does deep dives into how to get the most out of the program. Plus the guy is really entertaining.
The Skeptics Guide to the Universe (podcast and book)!
It depends on whether you are talking about formal logic or informal logic. For most of us we leaned formal logic in two ways. The first is we sat in some class called “Logic” under a “PHI” code and we learned *mainly* Aristotelian logic. That centers around the idea of a ‘syllogism’, which is a statement that is deductive and has exactly two premises and one conclusion. The definition of paradox is then very simple, it is the condition where the conclusion of your two premises invalidates one of the premises or produces a result that is absurd. When you understand that, you *get* why Bertrand Russel’s paradox invalidated naive set theory. You *get* time travel paradoxes.
The second set of formal logics we are exposed to is the study of geometry – to include trigonometry. In that, when given a series of demonstrable axioms you can draw conclusions using those axioms of arguments. When (I am not sure if you did this in school) you were given shapes and a conclusion, and you were asked to prove it, you were exercising logic. When you work with sines and cosines, you are exercising logic.
A formal fallacy is one where the structure invalidates the argument;
1. Affirming the consequent
2. Denying the antecedent
3. Affirming a disjunct
4. Denying a conjunct
5. Fallacy of the undistributed middle
6. Fallacy of 4 terms
Oddly enough, a formal error only invalidates the structure, you can have a condition where the argument structure is **valid** but the argument is **unsound**. In that case, one of both of the premises are false.
You quickly get into using Venn diagrams and truth tables in formal logic, where you start hitting abstractions people won’t care about. They are useful in mathematical and computational applications, so if you are studying computer science (as I have) you see these things again.
If you really, really, really, really want to learn – sign up for classes at your local community college. You can certainly self teach this topic if you really want, but I think philosophies are one of those subjects that is best learned by sitting in class.
If you’re after the “classic” Aristotelian logic, you’re going to best be served by enrolling in a course at your local community college, tbh. A neutral forum to talk with others about the subject is invaluable.
Logic was one of my favorite philosophy courses I ever took. You can also look into taking an Argumentation and Debate course after, or concurrently. It’s a solid forum to try and put concepts from logic into practice. I had a ton of fun in both courses.
Ethics is also an entertaining subject and will really get into some classic philosophical inquiry. Just barely eeks out above logic for my favorite philosophy course ever. To this day there are still some things I’m not emotionally fond of, but logically and ethically support. It’s an interesting inner conflict, and I credit both logic and ethics with my current therapy bills.
Go on any mooc website and type in “critical thinking course” . Here’s one: https://www.futurelearn.com/courses/logical-and-critical-thinking
At this point I think I’d favor Neil deGrasse Tyson’s masterclass on scientific thinking and communication. You’d get a good dose of logic and reasoning from a different perspective than from a philosophy course and it would be a lot of fun.
>I am really interested in the topic of using logic to make conclusions and opinions that are solid.
This is a common misconception. We don’t use logic to form conclusions and opinions. The method for that is dialectics, not logic. Logic is used to analyze and formalize a conclusion after the fact. The hard part of reaching valid conclusions isn’t scrutinizing if they are logically sound or not, but if their premises are valid and correspond to reality. If you try to use logic to form conclusions without a previous dialectical exam, you will end like the Analytical School nerds, who can spend hours dissecting the minute details of every single word in a proposition, but can’t even tell if it refers to something real or not.
>And then we have logical fallacies which are also interesting.
Yes, they are interesting, but also surrounded by misconceptions, thanks to the internet trolls who think memorizing a list of logical fallacies turns you into a skilled logician or formidable debater. In the same way you use logic to analyze and formalize a conclusion, logical fallacies are used to categorize errors after that process of formalization. A valid proposition can have the same structure of a logical fallacy, so if you fetishize logical fallacies in the way people on the internet often do, you’ll automatically become unable to understand any valid proposition that resembles one.
>I was going to ask for good books on the topic
The only way to avoid making the mistakes I pointed out above is to first understand the role of each form of discourse, rhetorical, dialectical, analytical, and poethical. There are no shortcuts for that. You need to start from the Aristotelian Organon and slowly move your way forward.
Dry logic doesn’t trump intuition, instinct, your gut feelings and creativity. You gotta have right and left brain both, an analytical mind on the left utilizing data, a creative instinctual mind on the right, making sh7t up as you go along.