Syllogism
Syllogism is a core topic in logical reasoning and general intelligence. It tests how you use given facts to reach a sure conclusion. In these questions, you get a set of 'Statements' followed by 'Conclusions.' Your primary task is to treat every statement as 100% true. You must do this even if the statements go against common sense or real-world facts. For example, a statement might say 'All birds are cars.' You must accept this as a fact for the duration of the question.
Concepts (2)
Sometimes, two conclusions are given where neither is 100% certain on its own. However, one of them must be true. This is called an 'Either-Or' case. It happens when: 1. Both conclusions have the same subject and predicate. 2.
Sometimes, two conclusions are given where neither is 100% certain on its own. However, one of them must be true. This is called an 'Either-Or' case. It happens when: 1. Both conclusions have the same subject and predicate. 2. Both conclusions are individually false. 3. One is positive (Some/All) and one is negative (No/Some Not). Example: Conclusion I: 'Some pens are red.' Conclusion II: 'No pen is red.' If they aren't certain, the answer is 'Either I or II follows.'
This is the most popular way to solve Syllogisms. You represent each category (like 'Pins' or 'Markers') as a circle. For 'All A are B,' draw circle A inside B. For 'Some A are B,' draw the circles overlapping.
This is the most popular way to solve Syllogisms. You represent each category (like 'Pins' or 'Markers') as a circle. For 'All A are B,' draw circle A inside B. For 'Some A are B,' draw the circles overlapping. For 'No A is B,' draw them completely apart. This helps you see the logical connections clearly. Example: If 'All apples are fruits' and 'All fruits are sweet,' the diagram shows 'apples' inside 'fruits' and 'fruits' inside 'sweet.' Thus, all apples are definitely sweet.
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Start Lesson: Complementary Pairs (Either-Or)