Foundational Concepts in Logic and Critical Thinking
Logic: The Art of Correct Reasoning
Logic comes from the Greek word logos, which means the art or craft of speech. Logic is the area of philosophy that studies correct reasoning and sound judgment. Logicians study logic.
Reasoning Definitions and Examples
Inductive Reasoning
This kind of reasoning is based on “induction,” the process of observing particular things and making generalizations. It goes from the little picture to the big picture.
Example: My cat purrs. My friend’s cat purrs. My neighbour’s cat purrs. Garfield also purrs. Therefore, all cats must purr (“all cats” is a generalization).
Deductive Reasoning
This kind of reasoning is based on “deduction,” the process of drawing a specific conclusion from a general statement. It goes from the big picture to the little picture.
Example: All athletes work out in the gym. Sierra works out in the gym. Therefore, Sierra is an athlete (“Sierra” is a specific conclusion).
Argument Structure
Definitions and examples from textbook pages 35–37:
- Argument: One someone gives reasons to prove a point.
- Argument = Premise + Conclusion
- Premise: Reasons or evidence given to support your conclusion.
- Conclusion: The claim the argument is trying to prove.
Fallacies in Reasoning
Fallacy Definition
An incorrect way of reasoning; an argument that does not follow logically from the evidence given. There are two types: formal fallacies and informal fallacies.
Formal Fallacies
A fallacy based on the incorrect form of an argument.
Hasty Generalization
The fallacy of basing an inductive argument on insufficient observations or an unrepresentative sample (too few observations to draw a sound conclusion).
Example: The grocery store worker I saw at FreshCo is a high school student. The grocery store worker I saw at No Frills is a high school student. The grocery store worker I saw at Metro is a high school student. Therefore, all grocery store workers are high school students.
Forgetful Induction
The fallacy of failing to take into account all the relevant evidence bearing on a conclusion (failing to take an important factor into account).
Example: Last week, I drank milk and got sick. This week, I drank milk and got sick. Therefore, all milk makes me sick. (Fallacy in logic: Did you take all factors into account? If the milk was expired, that would be the reason it made me feel sick, and not that all milk makes me sick.)
False Cause
Definition: The fallacy of arguing that since one event or condition was present before another, the earlier event or condition must be the cause of the later one (Attributing the wrong cause to something just because it came before).
Example: I wore my purple socks to school on the day I got a high mark on my Philosophy test. It must be because I wore my purple socks. (Fallacy in logic: I think I got a good mark because I wore purple socks, and not because I studied.)
Informal Fallacies
Mistakes in argument not based on mistakes in form, but on arguments that attempt to persuade emotionally or psychologically, but not logically.
Appeal to Emotion
This fallacy appeals to the emotion of the audience to try to win an argument, and not logic.
Example: Christmas is the best holiday. As a kid I couldn’t wait to open presents and eat Christmas dinner. That is why the best holiday is Christmas.
Appeal to Authority
This fallacy attempts to establish a claim by appealing to an unqualified expert or irrelevant authority.
Example: Elon Musk would be an excellent Presidential candidate because he is a successful businessman and an excellent engineer.
Ad Hominem Argument
This fallacy attacks the person making the claim instead of addressing the issue.
Example: Some English voters didn’t vote for Boris Johnson because his hair is messy and he looks like a slob, and that means he wouldn’t be a good Prime Minister.
Argument from Ignorance
This fallacy claims that because there is no evidence that something is false, then it must be true.
Example: There is no proof that sugary foods cause skin problems, so it must not be true.
Begging the Question
This fallacy is a circular argument in which the premises used to prove a conclusion already assumes the conclusion is true.
Example: “What she claims must be true because she always speaks the truth.”
Philosophical Concepts
Plato’s Allegory of the Cave Identification
Analysis of the elements:
- Sunlight: Truth and ultimate knowledge
- Darkness of the cave: Ignorance or limited practices
- Shadows: False beliefs or illusions
- People who stay in darkness: Those who refuse to question their assumptions
- Person who frees the chained one: A philosopher or guide helping others see reality
- Journey upwards: The difficult process of learning, self-discovery, and enlightenment
My Identification: I think I am a prisoner because I am still recognizing myself and still learning and questioning assumptions.
Philosophy as Activity
- Philosophy is an activity: The freed prisoners actively seek truth.
- Hardwork: Leaving the cave is difficult and requires effort and courage.
- Aim is freedom: The goal is mental and intellectual liberation.
- Examines basic assumptions: The prisoners question the shadows, realizing they are not reality.
Holiness
- Definition: Holiness is living morally, aligning actions with what is good, and showing devotion to truth or higher principles.
- Example of a holy person: Someone like a local spiritual figure or grandparents with experience.
- Three Core Qualities: Compassion towards each other, Integrity and moral consistency, Selflessness or devotion to a higher purpose.
Justice
- Definition: Justice is fairness, protecting rights, and serving the common good.
- Example of a just person: A judge, activist, or leader who defends fairness.
- Three Core Qualities: Fairness in decisions, Courage to stand up for what is right, Consistency in treating people equally.
Laws and Justice
- Good Laws: Promote fairness, protect rights, and serve the common good.
- Bad Laws: Unfair, arbitrary, or harm people.
- General Qualities: Good laws reflect justice and morality; bad laws reflect corruption or bias.
Argument on Good Laws:
Premise 1: A law should promote the well-being and fairness for all.
Premise 2: Laws that are unfair or harmful violate this principle.
Premise 3: Laws that reflect moral values and protect rights create trust and order.
Conclusion: Therefore, a good law promotes fairness, protects rights, and aligns with moral values, while a bad law fails to do so.
Autonomy
- Definition: Autonomy is the ability to make your own decisions and govern your own life.
- Importance for young people: Pursuing autonomy helps you think independently, take responsibility for your actions, and grow into a self-directed adult.
- Plato’s allegory of the cave: Autonomy is shown when a prisoner escapes the cave, sees reality, and chooses knowledge over ignorance.
- Unit’s contribution: Learning philosophy teaches critical thinking and self-reflection, which help make independent choices.
- Socrates’ role: Encouraged people to question assumptions and think for themselves, guiding them toward intellectual independence.