Science, Theories, and Models

What is science good for anyway?
- If we have a better understanding of how things work, we can build things or manipulate the world in such a way that we improve the quality of life.
- We're curious creatures; we want to know what makes things work. especially ourseives.
Phenomena, behaviors
- Kinds of phenomena
  1. - How two or more variables correlate with each other
      - Voting behavior: position on abortion, position on death penalty, position on amount of defense spending, party usually voting for
    - How one variable causes changes in another
      - Television violence and violent behavior
      - Red wine drunk and lessened risk of heart disease
    - How the system changes over time
      - The time course of a disease
      - The behavior of an object which is thrown against the ground
  2. - Physical, biological, cognitive, social phenomena; different levels
    - Why distinguish the levels (why not all physical)?
      Different levels require different elements for description or explanation.
      Imagine describing or explaining the religious practices of some ethnic group (a phenomenon at the social level) in terms of the molecules of their bodies and the objects around them (elements at the physical level).
  3. - Qualitative and quantitative phenonema
      - Qualitative: children not exposed to language before puberty fail to learn grammar.
      - Quantitative: Children learn an average of 9 words a day between the ages of 5 and 9.
  4. Phenomena of interest in this class
    - The way in which animals walk
    - The way in which people identify the meter in a simple rhythmic pattern or a piece of music
    - The way in which people produce the rhythm in a simple pattern or a piece of music
    - The way in which people learn to identify or produce rhythmic patterns
    - The nature of the rhythmic patterns in language: how they are identified, produced, learned

Abstracting away from details, describing the phemonenon in terms of a small number of variables

In describing and explaining the perception of musical meter, consider the effect of tempo, beat intensity, etc., but not the temperature of the room or the mood of the subject

Focusing in on subproblems

Appreciating a piece of music (too large to study) vs. finding the meter in a piece of music
Listening to a piece of music (too large) vs. listening to a simple rhythmic pattern

Description (what) and explanation (why)

Description: Democratic political systems oscillate between periods of more liberal and more conservative periods.
Explanation: Party systems make one sort of view clearly dominant at a given time. People tend to blame the current government for problems, which always exist, so whichever party is in power will not stay there long.
But there is not always agreement on what counts as explanation.

Comparing and evaluating explanations (theories)

Multiple explanations (theories) for the same phenomenon
- Theory of Gravitation vs. a theory by which all objects are attracted to the earth
- Theory of Evolution vs. Creationism
Handling the data: the theory must account for the facts
Single explanations of multiple phenomena
- Gravitation: objects falling to earth, objects floating on the surface of water, planetary orbits
- Theory of memory for music and language vs. one that works just for music
- Theory of animal gaits that handles the gaits of all animals, not just those of 4-legged animals
Independent motivation
- A theory of meter perception which makes use of a short-term memory, which is required anyway for psychological theories outside of meter. The short-term memory idea has independent motivation.
- A theory of gaits which posits oscillators in the brain. We already have reason to believe that there are oscillators in the brain.
Emergent behavior: a theory explains a higher-level behavior in terms of a lower-level one; the higher-level behavior "emerges" from the interaction of simple processes at the lower level
- Termite nest building: The termites seem to require a central control and details instructions for each of their roles, but the behavior is explainable in terms of the interaction of very simple behaviors of individual termites.
Simplicity, "elegance": Prefer theories that involve fewer variables and few mechanisms.
Comprehensibility: Prefer theories which are easier for people to understand.
- Complete instructions for how to build a cockroach at the level of individual cells would not be a very good theory of the cockroach.

Predictions from a model, hypotheses, and experiments

Mathematical models

Computer models, computer programs, algorithms, and experiments with the model