Does studying formal logic improve logical reasoning?

Question

I am looking to see if there is any good empirical evidence or study that shows or suggests that studying formal logic, or maybe informal logic, would actually improve skills at logical reasoning (using deductive or inductive reasoning)?

Here is a study I found but I know nothing about how to assess the validity or interpreting results:

https://dspace.lboro.ac.uk/dspace-jspui/bitstream/2134/21445/5/InglisPME40RR.pdf

Is this an accepted method of testing on this topic or is there a more accepted test? If you could also explain the results to answer my question I would appreciate it.

Answer 1

Though the quality of available evidence is not great, several reviews of deductive and inductive logic training programs do concur that studying logic can translate to improved logical reasoning (Klauer & Meiser, 2007; Nisbett, 1993; Hatcher, 1999; Perkins & Salomon, 1989; Baron, 2008 - pp42-44). However, purely formal logic training is not typically effective (Inglis & Attridge, 2016). Rather, training programs incorporating informal logic and real-world examples, are more likely to transfer to general logical reasoning skills.

Additional constraints on the effectiveness of logic training include:

• Teaching subject matter to an appropriate audience - ie, old enough, competent enough, sufficiently experienced, etc.
• Selecting effective subject matter for generalization - eg, language syllogisms, common biases, pragmatic schemas, etc.
• An adequate classroom environment - eg, social interactions, competent teacher, self-learning opportunities, etc. Modern approaches often incorporate software tools (Astleitner, 2002).
• Evaluating results using appropriate measures - eg, domain-general questions, real-world examples, validated tests, etc.

This question is part of a larger debate about how much learned skills generalize to other domains - known as the theory of formal discipline and transfer of learning. It is also part of a question about how best to teach critical thinking skills more broadly, of which logical reasoning is a component.

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The study cited in the question - Attridge, Aberdein, & Inglis (2016) - does indeed test whether a course in logic improves logical reasoning. It also includes a brief review of some previous attempts. The experimental design uses a controlled trial method, but notably, it is not a randomized controlled trial (RCT), limiting the definitiveness of its conclusions. It does suggest that prior experience, as well as the measure used, affect the results of training.

As a general heuristic, I would not update too much on a single study anyhow, and always prefer to look for tertiary sources (textbook, encyclopedia) or secondary sources (literature review, meta-analysis) over primary sources (experimental study, theoretical work).

Answer 2

I think the answer is pretty obvious. Formal logic would definitely help with logical reasoning.

The shortcoming of formal logic is it isn't a robust method of argument. It can't be used in real-life debates. For example, an appeal to authority shouldn't invalidate an argument because a person's credentials should matter. If we had to judge everything but its merit, nothing would get done. It would make work too inefficient. If an author didn't list his credentials, we would have to wade through hundreds of research papers before we found a good one.

Despite the above, I believe formal logic is a great way to get the mind working especially for children. You just need to emphasize that formal logic doesn't work in a real debate. I frequently see adults cite logical fallacies falsely assuming their use of formal logic is dispositive.