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Principles of logical reasoning, judgement and types of evidence

Evidence, judgement, and logical reasoning

In order to avoid errors and fallacies in logical reasoning, a few principles can be followed. These are not to be considered as rules, but as pieces of advice (Dowden, B., D., 2011/ 2019):

  1. Conclusions must be based on reasons/ arguments;
  2. Offer reasons in accordance to your audience characteristics;
  3. The offered reasons should imply the conclusion;
  4. Base your arguments on relevant information;
  5. “Weigh the pros and cons”;
  6. Take into consideration the alternatives and their consequences, but also the probability that consequences could happen;
  7. Use your previous knowledge and common sense for your conclusions;
  8. Seek for a second opinion;
  9. Be consistent;
  10. Stick to the subject”;
  11. Draw your conclusion only based of enough evidence.

Evidence needs to be reliable, in order to accept the arguments. Different types of evidence can be invoked, in accordance to the type of situation (

  1. Reports: data, details, case studies, statistics, official reports;
  2. Experts’ opinions;
  3. Laws
Principles of logical reasoning, judgement and types of evidence

Methodology and Resources

  • Dowden, B. D. [2011] (2019). Logical Reasoning. Philosophy Department. California State University Sacramento. CA 95819 USA. Available at: CSUS  Accessed on 24.01.2020
  • Reasoning. Monash University. Available at: Monash. Accessed on 25.01.2020