Reasoning
Logic and Fallacies
1,803 Questions
Understand the fundamentals of propositional logic, logical inference rules, and paradoxes. This set includes identifying logical fallacies, including those found in classical Nyaya logic. Strong grasp of these concepts is crucial for scoring well in the reasoning sections of competitive tests.
Propositional logic modelsLogical inference rulesTypes of logical fallaciesParadoxes and contingent truthsNyaya logic concepts
Logic and Fallacies Questions
Which of the following statements is a logical fallacy?
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All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
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All birds can fly. This creature has wings. Therefore, this creature can fly.
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All metals are good conductors of electricity. Therefore, copper is a good conductor of electricity.
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All triangles have three sides. Therefore, this shape with three sides is a triangle.
C
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all metals are good conductors of electricity, and the conclusion states that copper is a good conductor of electricity. However, the fact that copper is a good conductor of electricity does not necessarily mean that it is a metal. There are many other materials that are also good conductors of electricity, such as graphite, salt water, and human skin.
Which of the following statements is a logical fallacy?
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All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
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All birds can fly. This creature has wings. Therefore, this creature can fly.
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All roses are red. This flower is red. Therefore, this flower is a rose.
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All triangles have three sides. Therefore, this shape with three sides is a triangle.
B
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all birds can fly, and the conclusion states that this creature can fly. However, the fact that this creature has wings does not necessarily mean that it can fly. There are many creatures that have wings but cannot fly, such as penguins, ostriches, and emus.
Which of the following statements is a logical fallacy?
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All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
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All birds can fly. This creature has wings. Therefore, this creature can fly.
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All roses are red. This flower is red. Therefore, this flower is a rose.
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All triangles have three sides. Therefore, this shape with three sides is a triangle.
A
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all dogs are mammals, and the conclusion states that this animal is a mammal. However, the fact that this animal is a dog does not necessarily mean that it is a mammal. There are many other animals that are not mammals, such as birds, reptiles, and amphibians.
Which of the following statements is a logical fallacy?
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All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
-
All birds can fly. This creature has wings. Therefore, this creature can fly.
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All roses are red. This flower is red. Therefore, this flower is a rose.
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All triangles have three sides. Therefore, this shape with three sides is a triangle.
D
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all triangles have three sides, and the conclusion states that this shape with three sides is a triangle. However, the fact that this shape has three sides does not necessarily mean that it is a triangle. There are many other shapes that also have three sides, such as squares, rectangles, and hexagons.
Which of the following statements is a logical fallacy?
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All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
-
All birds can fly. This creature has wings. Therefore, this creature can fly.
-
All roses are red. This flower is red. Therefore, this flower is a rose.
-
All triangles have three sides. Therefore, this shape with three sides is a triangle.
C
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all roses are red, and the conclusion states that this flower is a rose. However, the fact that this flower is red does not necessarily mean that it is a rose. There are many other types of flowers that are also red, such as tulips, poppies, and carnations.
Which of the following statements is a logical fallacy?
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All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
-
All birds can fly. This creature has wings. Therefore, this creature can fly.
-
All metals are good conductors of electricity. Therefore, copper is a good conductor of electricity.
-
All triangles have three sides. Therefore, this shape with three sides is a triangle.
C
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all metals are good conductors of electricity, and the conclusion states that copper is a good conductor of electricity. However, the fact that copper is a good conductor of electricity does not necessarily mean that it is a metal. There are many other materials that are also good conductors of electricity, such as graphite, salt water, and human skin.
Which of the following statements is a logical fallacy?
-
All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
-
All birds can fly. This creature has wings. Therefore, this creature can fly.
-
All roses are red. This flower is red. Therefore, this flower is a rose.
-
All triangles have three sides. Therefore, this shape with three sides is a triangle.
B
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all birds can fly, and the conclusion states that this creature can fly. However, the fact that this creature has wings does not necessarily mean that it can fly. There are many creatures that have wings but cannot fly, such as penguins, ostriches, and emus.
Which of the following statements is a logical fallacy?
-
All dogs are mammals. This animal is a dog. Therefore, this animal is a mammal.
-
All birds can fly. This creature has wings. Therefore, this creature can fly.
-
All roses are red. This flower is red. Therefore, this flower is a rose.
-
All triangles have three sides. Therefore, this shape with three sides is a triangle.
A
Correct answer
Explanation
This is a logical fallacy known as affirming the consequent. The premise states that all dogs are mammals, and the conclusion states that this animal is a mammal. However, the fact that this animal is a dog does not necessarily mean that it is a mammal. There are many other animals that are not mammals, such as birds, reptiles, and amphibians.
Which of the following is NOT a type of reasoning?
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Deductive reasoning
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Inductive reasoning
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Abductive reasoning
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Analogical reasoning
C
Correct answer
Explanation
Deductive reasoning is the process of drawing conclusions from general principles. Inductive reasoning is the process of drawing conclusions from specific observations. Analogical reasoning is the process of drawing conclusions based on similarities between two things. Abductive reasoning is not a type of reasoning.
Which Pramana is based on reasoning and logical deduction?
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Perception
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Inference
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Comparison
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Testimony
B
Correct answer
Explanation
Inference is the Pramana that is based on reasoning and logical deduction.
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A hypothesis is a statement that is assumed to be true for the purpose of testing
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A hypothesis is a statement that is known to be true
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A hypothesis is a statement that is not supported by evidence
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A hypothesis is a statement that is not falsifiable
A
Correct answer
Explanation
A hypothesis is a statement that is assumed to be true for the purpose of testing. It is a tentative explanation for a phenomenon that is based on evidence and observation. Hypotheses are tested through research studies to determine if they are supported or refuted.
Which of the following is an example of a necessary condition that is not a cause?
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The presence of oxygen for a fire to start
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The presence of a spark for a fire to start
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The presence of fuel for a fire to start
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The presence of heat for a fire to start
A
Correct answer
Explanation
Oxygen is a necessary condition for a fire to start, but it is not a cause of the fire. The spark is the cause of the fire, as it is the event that brings about the fire.
Which of the following is an example of a sufficient condition that is not a cause?
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The presence of a spark for a fire to start
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The presence of fuel for a fire to start
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The presence of heat for a fire to start
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The presence of oxygen for a fire to start
C
Correct answer
Explanation
Heat is a sufficient condition for a fire to start, but it is not a cause of the fire. The spark is the cause of the fire, as it is the event that brings about the fire.
Which of the following is an example of a cause that is not a necessary condition?
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The presence of a spark for a fire to start
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The presence of fuel for a fire to start
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The presence of heat for a fire to start
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The presence of oxygen for a fire to start
A
Correct answer
Explanation
A spark is a cause of a fire, but it is not a necessary condition for a fire to start. A fire can start without a spark, if there is enough heat and fuel.
Which of the following is an example of a necessary condition that is not a sufficient condition?
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The presence of a spark for a fire to start
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The presence of fuel for a fire to start
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The presence of heat for a fire to start
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The presence of oxygen for a fire to start
D
Correct answer
Explanation
Oxygen is a necessary condition for a fire to start, but it is not a sufficient condition. A fire cannot start without oxygen, but it also needs fuel and heat.