Philosophy - Logic Resources
Logic: the organized body of knowledge, or science, that evaluates arguments. Principles that we may use as criteria for evaluating the arguments of others and as guides in constructing arguments of our own
Argument: a group of statements, one or more of which (the premises) are claimed to provide support for, or reasons to believe, one of the others (the conclusion).
Statement: a sentence that is either true/false. Some sentences do not fall onto this category: questions, proposals, suggestions, commands and exclamations
Inference: the reasoning process expressed by an argument
Deductive logic: Part of logic that concerns with tests of validity and invalidity
Inductive logic: Part of logic that concerns with tests for strengths and weakness
Conclusion indicators: therefore accordingly entails that wherefore we may conclude hence thus it must be that it follows that consequently for this reason implies that we may infer so as a result
Premise indicators: since in that seeing that as indicated by may be inferred from for the reason that because as in as much for given that owing to
Deductive: Conclusion can’t be false when the premise is true
- Involve necessary reasoning
- Math style
Example:
1. Categorical syllogism:
All ancient forests are sources of wonder.
Some ancient forests are targets of the timber industry.
Therefore, some sources of wonder are targets of the timber industry.
2. Hypothetical syllogism:
If Fox News is a propaganda machine, then it misleads its viewers.
Fox News is a propaganda machine.
Therefore, Fox News misleads its viewers.
3. Disjunctive syllogism:
Either global warming will be arrested, or hurricanes will become more intense.
Global warming will not be arrested.
Therefore, hurricanes will become more intense.
Inductive: Improbable that the conclusion is false, when the premise is true
- Probabilistic reasoning
Example:
1. Prediction:
Argument: a group of statements, one or more of which (the premises) are claimed to provide support for, or reasons to believe, one of the others (the conclusion).
Statement: a sentence that is either true/false. Some sentences do not fall onto this category: questions, proposals, suggestions, commands and exclamations
Inference: the reasoning process expressed by an argument
Deductive logic: Part of logic that concerns with tests of validity and invalidity
Inductive logic: Part of logic that concerns with tests for strengths and weakness
Conclusion indicators: therefore accordingly entails that wherefore we may conclude hence thus it must be that it follows that consequently for this reason implies that we may infer so as a result
Premise indicators: since in that seeing that as indicated by may be inferred from for the reason that because as in as much for given that owing to
Deductive: Conclusion can’t be false when the premise is true
- Involve necessary reasoning
- Math style
Example:
1. Categorical syllogism:
All ancient forests are sources of wonder.
Some ancient forests are targets of the timber industry.
Therefore, some sources of wonder are targets of the timber industry.
2. Hypothetical syllogism:
If Fox News is a propaganda machine, then it misleads its viewers.
Fox News is a propaganda machine.
Therefore, Fox News misleads its viewers.
3. Disjunctive syllogism:
Either global warming will be arrested, or hurricanes will become more intense.
Global warming will not be arrested.
Therefore, hurricanes will become more intense.
Inductive: Improbable that the conclusion is false, when the premise is true
- Probabilistic reasoning
Example:
1. Prediction: