Philosophy: Ethics, Logic & Critical Thinking

# Philosophy: Ethics, Logic & Critical Thinking

## Formal Logic Foundations

### Argument Structure
Every arg consists of prem (supporting claims) and a conc (the claim being supported). A val arg has a logical structure where IF the prem are true, the conc MUST be true. A snd arg is val AND has actually true prem. Critical distinction: val is about structure, snd is about structure + truth.

Example of val but unsnd:
- Prem 1: All cats can fly
- Prem 2: Socrates is a cat
- Conc: Socrates can fly
Structure is perfect (val), but Prem 1 is false (unsnd).

### Deductive vs Inductive
Deductive args guarantee conc if prem are true. The conc contains no information not already in the prem — it makes implicit information explicit. Syllogisms are the classic form: All A are B, X is A, therefore X is B.

Inductive args provide probable but not certain conc. emp observation leads to generalizable claims: "Every swan I've observed is white, therefore all swans are white." The problem of induction (Hume): no amount of observation logically guarantees the next case. Science operates inductively — theories are never proven, only not-yet-falsified (Popper's falsificationism).

### Common Fal

**Formal fal** (structural errors):
- Affirming the consequent: If P then Q; Q; therefore P. (If it rains, streets are wet. Streets are wet. Therefore it rained. — Could be a broken hydrant.)
- Denying the antecedent: If P then Q; not P; therefore not Q. (If I study, I'll pass. I didn't study. Therefore I'll fail. — Could pass anyway.)

**Informal fal** (content errors):
- Ad hominem: Attacking the person instead of the arg. "You can't trust his climate research — he drives an SUV." The arg's merit is independent of the arguer's behavior.
- Straw man: Misrepresenting someone's arg to make it easier to attack. Rebut the actual position, not a distortion.
- Appeal to authority: Expert opinion supports but doesn't prove. Experts can be wrong, biased, or speaking outside their expertise.
- False dilemma: Presenting only two options when more exist. "You're either with us or against us" ignores neutrality, partial agreement, etc.
- Slippery slope: Claiming one event inevitably leads to extreme consequences without establishing the causal chain.
- Circular reasoning (begging the question): The conc is assumed in the prem. "God exists because the Bible says so, and the Bible is true because it's God's word."
- Tu quoque: "You do it too" — someone's hypocrisy doesn't invalidate their arg.
- Composition/Division: What's true of parts isn't nec true of the whole (and vice versa).

## Epistemology: Theory of Knowledge

### What is Knowledge?
Classical definition (Plato): Knowledge = Justified True Belief (JTB). You know prop P if: (1) P is true, (2) you believe P, (3) you have justification for P.

Gettier problems (1963) shattered JTB: Cases where someone has justified true belief but clearly doesn't "know." Example: You see what looks like a sheep in a field (it's actually a dog in a sheep costume), but there IS a real sheep hidden behind a hill. Your belief "there's a sheep in the field" is justified and true — but it seems wrong to call it knowledge. This spawned decades of attempts to add a fourth condition.

### Sources of Knowledge
- **emp knowledge** (a posteriori): Derived from sensory experience. "Water boils at 100°C at sea level." Can be revised by new observations.
- **rat knowledge** (a priori): Known through reason alone, independent of experience. "2 + 2 = 4" and "All bachelors are unmarried" are true by definition/logic.
- **Testimony**: Most of what we "know" comes from others — teachers, books, news. Raises questions about trust, authority, and the social nature of knowledge.

### Skepticism
Descartes' method of doubt: What can I know with absolute certainty? Sensory experience can deceive (illusions, dreams). Mathematics seems certain but could be manipulated by an evil demon. Only "I think, therefore I am" (cogito ergo sum) survives — the act of doubting proves a thinking entity exists.

Practical response: Absolute certainty is an unreasonable standard. We navigate reality using degrees of confidence calibrated to evidence. The question isn't "Am I certain?" but "How well-supported is this belief?"

## Eth Theory: Major Frameworks

### Consequentialism (util)
Actions are mor right or wrong based solely on their outcomes. The most influential version is util: the right action produces the greatest good for the greatest number.

**Bentham's quantitative util**: Calculate pleasure minus pain across all affected parties. Pleasures differ in intensity, duration, certainty, proximity, fecundity (likelihood of producing more pleasure), and purity.

**Mill's qualitative util**: Some pleasures are higher (intellectual, aesthetic) than others (bodily). "It is better to be Socrates dissatisfied than a fool satisfied." This addresses the objection that util reduces morality to crude hedonism.

**Problems with util**: (1) Impossible to calculate all consequences. (2) Allows horrifying acts if they maximize aggregate welfare — torturing one innocent person to save five? (3) Ignores justice and rights — a society could enslave a minority if the majority benefits enough. (4) Demandingness objection: if you should always maximize good, you must give away most of your income to charity rather than buy anything non-essential.

### Deon Ethics (Kant)
Actions are mor right or wrong based on whether they follow mor rules/duties, regardless of consequences. Kant's Categorical Imperative has three formulations:

1. **Universalizability**: Act only according to rules you could will as universal laws. Lying fails: if everyone lied, trust would collapse, making lying pointless — a cont.
2. **Humanity as end**: Treat people never merely as means but always also as ends in themselves. Using someone purely as a tool for your goals violates their rational autonomy.
3. **Kingdom of Ends**: Act as if you were legislating for a community of rational agents who all follow the same principles.

**Problems with deon**: (1) Rigid rule-following can produce terrible outcomes — Kant argued you must not lie to a murderer asking where your friend is hiding. (2) When duties conf (don't lie vs. protect the innocent), the framework offers limited guidance. (3) The universalizability test can be gamed by making rules specific enough to always pass.

### Vir Ethics (Aristotle)
Focus on character rather than actions or rules. The right action is what a virtuous person would do. Vir are character traits developed through practice — courage, temperance, justice, wisdom, honesty, compassion.

Aristotle's doctrine of the mean: each vir is a balance between excess and deficiency. Courage is the mean between cowardice (deficiency) and recklessness (excess). Generosity is the mean between miserliness and prodigality.

Eudaimonia (flourishing/well-being) is the ultimate aim — not a feeling but an activity of living well and doing well over a complete life. Vir are nec for eudaimonia but may not be suf — Aristotle acknowledged that external goods (health, resources, relationships) also matter.

**Problems with vir eth**: (1) Limited action-guidance — "be virtuous" doesn't tell you what to do in a specific dilemma. (2) Cultural rel — virtues valued in one culture may not be valued in another. (3) Moral luck — your character is shaped by upbringing and circumstances you didn't choose.

### Care Ethics
Developed by Gilligan and Noddings as an alternative to justice-focused frameworks. Morality is rooted in relationships and responsiveness to others' needs, not abs principles. Emphasizes: attentiveness (noticing others' needs), responsibility (responding to those needs), competence (caring effectively), and reciprocity.

Strength: captures the mor significance of personal relationships that principle-based eth struggle with. Weakness: can become parochial — favoring those close to us at the expense of strangers.

## Critical Thinking Applied

### Cog Biases
Systematic errors in thinking that affect judgment:

- **Confirmation bias**: Seeking/interpreting evidence to confirm existing beliefs, ignoring disconfirming evidence. The most pervasive and dangerous bias. Antidote: actively seek evidence against your position.
- **Anchoring**: Over-relying on the first piece of information encountered. First number in a negotiation sets the frame.
- **Availability heuristic**: Judging probability by how easily examples come to mind. Plane crashes are memorable, so flying feels dangerous (it's statistically the safest transport).
- **Dunning-Kruger**: Low-competence individuals overestimate their ability; high-competence individuals underestimate theirs. Knowledge of a field reveals how much you don't know.
- **Sunk cost fal**: Continuing an endeavor because of previously invested resources rather than future prospects. Past costs are irrelevant to future decisions.
- **Bandwagon effect**: Adopting beliefs because many others hold them. pop of a belief has no bearing on its truth.
- **Framing effect**: Decisions change based on how options are presented. "90% survival rate" feels different from "10% mortality rate" — same information, different response.

### Evaluating Claims
A systematic approach to any claim:

1. **Clarify**: What exactly is being claimed? Vague claims can't be evaluated.
2. **Evidence**: What evidence supports it? Is it emp, testimonial, rat? How strong?
3. **Source**: Who's making the claim? What expertise do they have? What incentives might bias them?
4. **Alternatives**: What other explanations fit the evidence? Have they been ruled out?
5. **Consistency**: Does it contradict well-established knowledge? Extraordinary claims require extraordinary evidence.
6. **Falsifiability**: Could any evidence prove it wrong? Unfalsifiable claims aren't worthless but fall outside emp investigation.

### Argument Mapping
Visualize arg structure to identify strengths and weaknesses:
- State the main conc
- Identify each prem supporting it
- For each prem, ask: Is it true? Is it relevant? Does it suf support the conc?
- Identify implicit (unstated) prem — these are often the weakest links
- Check for fal in the reasoning chain
- Evaluate whether the prem collectively provide suf support even if individually each is reasonable

### Steel-Manning
The opposite of straw-manning: present the strongest possible version of an opposing arg before critiquing it. This practice: (1) ensures you understand the position you're arguing against, (2) makes your rebuttal more credible, (3) sometimes reveals your own position is weaker than you thought, (4) models intellectual honesty.

Principle of charity: interpret ambiguous statements in their most reasonable form. Assume your interlocutor is rat and well-intentioned unless proven otherwise. Productive disagreement requires this foundation.