Plato's Symposium · Aristotle's Four Causes · Basic Logic and Fallacies

Week 3 · Week 3: Plato's Symposium · Aristotle's Four Causes · Basic Logic and Fallacies · Ch. 2: How Philosophy is Done, Ch. 3: Ancient Philosophy, Ch. 8: Love and Happiness · Download .docx

Objectives

Summarize Diotima's ladder of love from the Symposium
Apply Aristotle's Four Causes to at least three different objects
Distinguish valid from sound deductive arguments
Identify and name eight common logical fallacies with examples

Key terms

Eros: Love as desire — the subject of every speech in the Symposium.
Diotima's ladder: The climb from loving one beautiful body to loving Beauty itself — Socrates' account of love.
Material cause: What a thing is made of.
Formal cause: The shape, pattern, or definition that makes a thing what it is.
Efficient cause: The agent or process that brings a thing about.
Final cause: The purpose or end a thing is for.
Valid: A deductive argument whose conclusion must be true if its premises are true.
Sound: A valid argument with all true premises.
Ad hominem: Attacking the person instead of the argument.
Straw man: Misstating an opponent's view so it is easy to knock down.
False dilemma: Presenting two options as the only ones when others exist.
Begging the question: Assuming the conclusion inside a premise.

The concept

Three Ideas That Belong Together

Week 3 asks you to hold three ideas in your head at once: a theory of love from Plato, a theory of explanation from Aristotle, and the basic tools of logical analysis. They connect because the same demand — give me the real explanation, not a surface story — drives all three.

Diotima's Ladder of Love

In the Symposium, Socrates reports what a wise woman named Diotima taught him about love. Love is always desire for what one lacks — it is never satisfied for long, because satisfaction removes the lack that drove the desire. Diotima describes a ladder a philosophical lover can climb: love one beautiful body, then notice that all beautiful bodies share a quality and love that; then love beautiful souls; then love beautiful practices and laws; then love beautiful knowledge; and finally see Beauty itself — unchanging, pure, the Form of Beauty. Aristophanes told a different story: humans were once spherical beings split in two by Zeus, and love is each half searching for its other. Both speeches illuminate something real about longing.

Aristotle's Four Causes

Aristotle argues that to fully understand anything, you need four answers. The material cause answers 'What is it made of?' A bronze statue: bronze. The formal cause answers 'What shape or definition makes it this kind of thing?' The statue: the figure it represents. The efficient cause answers 'What brought it about?' The statue: the sculptor's work. The final cause answers 'What is it for?' The statue: to honor a hero. These four causes apply everywhere — to a heart (tissue; pump-shape; embryological development; pumping blood), to a school (buildings; curriculum; teachers and administrators; educating students). The final cause — purpose — is often the most revealing and the most contested.

Logic: Valid, Sound, and the Common Fallacies

An argument is a set of premises offered as reasons for a conclusion. Deductive arguments aim at validity: if all premises are true, the conclusion must be true. A valid argument with actually true premises is sound. Most everyday arguments are inductive — premises make the conclusion probable, not certain. Eight fallacies you need to spot: ad hominem (attack the person, not the argument); straw man (misstate the view to make it easy to knock down); false dilemma (only two options when others exist); slippery slope (one step leads to catastrophe — where is the evidence?); appeal to popularity (many people believe it, so it must be true); hasty generalization (a few cases prove a general rule); begging the question (the conclusion is hidden in a premise); red herring (change the subject). For your Major Essay 1: check your own draft for these errors before you submit.

Worked examples

Example 1: Example 1 — Four causes of a school's math class: Material cause: desks, whiteboards, textbooks, and the physical room. Formal cause: the structure of instruction — the curriculum that defines what a math class is (teaching arithmetic, algebra, proof). Efficient cause: the teachers who plan and deliver the lessons. Final cause: preparing students to reason quantitatively, pass exams, and use mathematics in their lives. Notice that the final cause tells you the most about what would make the class succeed or fail.

Example 2: Example 2 — Spotting fallacies in a debate: 'We should ban junk food in schools because everyone knows processed food is bad for you (appeal to popularity). Either we ban it or our students will be obese (false dilemma). Besides, Dr. Jones, who supports junk food, was once caught lying about his credentials (ad hominem). Allowing junk food leads to obesity, then diabetes, then a healthcare crisis (slippery slope).' Count: four fallacies in five sentences. The correct approach: argue from evidence about specific health effects of specific foods — premises that can actually be evaluated.

Common mistakes

Confusing the efficient and final cause — the efficient cause is what made something happen (the sculptor); the final cause is what it is for (honoring a hero).
Thinking a valid argument is automatically sound — an argument can be valid even if all its premises are false; soundness requires both validity and true premises.
Confusing ad hominem with any negative remark — ad hominem is specifically attacking the person to dismiss an argument; not every criticism of a person is a fallacy.
Confusing false dilemma with disagreement — false dilemma forces a choice between two options and ignores the others; the error is in the number of options offered, not in the disagreement itself.
Treating begging the question as meaning 'raising a question' — in logic it means smuggling the conclusion into a premise, making the argument circular.

Self-check

Try each one before you look. A miss here costs nothing and tells you exactly what to reread.

1. What does Diotima say love fundamentally is, and how does it differ from Aristophanes' account?

2. Apply Aristotle's four causes to a smartphone.

3. What is the difference between a valid argument and a sound argument?

4. Identify the fallacy: 'If we let students use phones in class, they will stop learning, then fail every test, then drop out, and society will collapse.'

5. What is the straw man fallacy and why is it dishonest?

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