Lecture #3 Feb 4 Jan 2010 What is Science?
Last time: Development of science includes tension between logic and observation/experiment.
Plato: distrust imperfect material world, use logic and intuition
Aristotle: logic (but also observation); hierarchal cosmos
Scholastics: Use Aristotle’s rhetoric to “find truth”
Bacon: distrust intuition, start from observation
Galileo, Newton: active experimentation, universal laws
Last time: Two kinds of discourse
Irreproducible: based on revelation, authority, argument alone
Reproducible: based on recipes that can be replicated by anyone (leads to science)
What do scientists want?
Scientists interested in convincing novelty:
-- new observations or theories
-- but must be able to convince others of their ideas
-- reproducible recipes: in principle, anyone can duplicate
-- outward skepticism towards authority
-- inward skepticism of one’s own ideas
Today: The mechanics of science
observation or experiment -> theory (a narrative about those observations) -> predict new observations
A theory of theories
A theory is a narrative or related narratives that help us to (a) organized established empirical facts and (b) make predictions about observations or experiments not yet carried out.
A good theory will (a) explain a large of already known facts
(b) within as simple a framework as possible
(c) make predictions about future facts
Falsifiability: A theory is “falsifiable” if all parties agree that certain outcomes would mean the theory is false. (due to Karl Popper)
“Just a theory”?
False dichotomy: “theory” vs. “law”
Better: how much evidence is there for a given theory?
Science and rhetoric
Scientists are (generally) mistrustful of heavy reliance upon argument and rhetoric alone
Nonetheless, theories and other “narratives” are needed to shape and guide inquiry.
Two views on science and rhetoric
Naēve realism: science is “just the facts” and rhetoric and culture play no role in science
Naēve idealism/rhetoricism: science is all culturally determined
Science and culture
Here culture = assumptions from politics, tradition, religion, etc.
Ideally, through skepticism and experimentation, science can reduce the influence of “culture.” Nonetheless, culture can have strong influence:
-- Limiting or directing the questions
-- Masking unquestioned assumptions
-- Rhetoric and argument overwhelm skepticism
Science is not culture neutral: science is guided by narratives and metaphors those narratives are influenced by culture. Nonetheless, science is not just a product of culture. Observation and experiment can and often do contradict cultural assumptions.
If this were not true, we would not have so many “surprising” scientific results:
Controversies in science vs. culture
Sometimes “controversies” in science are really collisions between scientific narratives (theories) and cultural narratives.
Narratives about science
Narratives about the nature of science
* science is about the “real world”
* science is a product of culture
Narratives about change in science
* science is smooth and continuous; builds upon past
* science has discontinous “revolutions”
old ideas completely overturned
3 models for scientific “progress”
1. Eternal growth
2. Eternal revolution
-- Science relies on repeatable recipes not authority or argument to settle issues
-- Modern science has an economy of novelty
→ focussed skepticism to get good return of novelty
(often many small payoffs rather than infrequent large payoffs)
-- Scientists wary of narratives (such as theories) but still use them to guide thinking, experiments
-- Scientists try to use skepticism to eliminate influence of culture
-- Cultural assumptions can still influence the questions scientists ask
Useful to look at narratives about science, in particular narratives regarding scientific progress: steady growth or revolution or plateau