Science

Science and the Scientific Method An Introduction for Paramedic Students What is Science? A set of facts and the theories that explain the facts. Science = being done by institutions carrying on “scientific” activity. A Whatever’s particular approach, the scientific method. Popular Fictions The goal of science is to accumulate facts Science distorts reality and can’t do justice to the fullness of human experience. Scientific knowledge is truth. Science is concerned primarily with solving practical and social problems. So then, what is Science? “Science is neither a philosophy nor a belief system. It is a combination of mental operations that has become increasingly the habit of educated peoples, a culture of illuminations hit upon by a fortunate turn of history that yielded the most effective way of learning about the real world ever conceived.” Edward O. Wilson Consilience: The Unity of Knowledge The Heart of the Matter Why do we see what we do and not something else? Mythos “The Word” An authoritative account of the facts that is not to be questioned. Thales of Miletus The Father of Greek Science, Philosophy, and Mathematics Man is capable of understanding nature. Natural phenomena have natural explanations. Logos “The Word” An account of the facts whose truth can be demonstrated and debated Aristotle Developed “logos” into “logic” Advocated deductive reasoning as a tool for understanding nature Dominated scientific thinking for the next 2000 years Deduction Reasoning from the general to the specific “All men are mortal.” (major premise) “Socrates is a man.” (minor premise) “Therefore, Socrates is mortal.” (conclusion) Always produces correct answers if the premises are correct. The Problems of Deduction The conclusions are only as good as the premises. Because it moves from general to specific cases, deduction does not generate new knowledge. The Problem with Aristotle He didn’t advocate the use of experiments or observations to check the validity of premises. He was a pure rationalist. “Thinking about it is good enough.” Francis Bacon  If you want to know how the world works, begin with the facts. Not prejudices about what the facts are.  Infer general instances from specific observations.  Draw conclusions about future events from past observations. Induction Reasons from the specific to the general Can generate new knowledge However, the accuracy of that new knowledge can NEVER be proven with 100% certainty WHY? Because we can never be 100% certain about what our next observation will show Galileo If you have a theory about how a phenomenon works, test it with an experiment. During an experiment, try to control all of the variables except the one you are interested in. Isaac Newton Mathematics is the language of nature. The world of observation can be encoded into mathematical form. Mathematical forms can be decoded into new statements about reality. The Scientific Method Hypothesis Empirical Law Observation Experiment Empirical Laws Are about kinds of events, not any single event Show relationships between two or more kinds of events Are supported by a large amount of experimental data Are applicable to a variety of different events An Example: Boyle’s Law In 1662, Irish chemist Robert Boyle studied the effects of pressure changes on the volume of gases. An Example: Boyle’s Law  His experimental results showed that as pressure increases, the volume of a gas decreases proportionately.  PV = constant  So, if we decrease the volume of a container, we can predict how much the pressure of the gas inside will increase. An Example: Boyle’s Law  Boyle’s work was later combined with that of Jacques Charles and Joseph Gay-Lussac to produce the Ideal Gas Law.  PV = nRT  The Ideal Gas Law predicts the behavior of gases over a wide range of temperatures, pressures, and volumes.  There’s just one problem: It doesn’t explain how this stuff works! We need a theory!!! A means of relating the laws describing a class of events to a framework and a set of principles described in terms differing from those used for the laws. The observations predicted by the Ideal Gas Law are explained by the Kinetic Theory of Gases. The Kinetic Theory of Gases Let’s assume that the molecules making up a gas are like little billiard balls... So, if we decrease the size of the container, what happens to the number of impacts? Wouldn’t that make the gas pressure equivalent to the number of impacts by the billiard balls with the sides of the container? What would happen to the number of collisions if we increased the velocity of the billiard balls? Isn’t increasing the velocity of the billiard balls equivalent to increasing the temperature of the gas? The Kinetic Theory of Gases Theory of Billiard Balls Kinetic Theory MODEL (Tiny elastic spheres) Observations on Billiard Balls Analogy? Analogy? Observations on Gases A Good Theory Is... Accurate Fruitful Consistent Simple Broad Why there are no scientific “truths” The Problem of Induction Hypotheses, laws, and theories are products of inductive reasoning Products of inductive reasoning are only as good as the next observation But it only takes one negative piece of data to refute it So, no amount of data will ever confirm a hypothesis, law, or theory Falsifiability “The scientific mentality may be roughly characterized as the tendency to suspend belief until evidence of the appropriate kind is produced. And then to believe the proposition in question to the degree that the available evidence warrants it, without excluding the possibility of a further disconfirmation.” Sir Karl Popper Norms of Science Originality Accessibility Detachment Skepticism Universality The Hallmarks of Pseudoscience Anachronistic Thinking Seeking Mysteries Appeals to Myths Irrefutable Hypotheses Casual Approach to Evidence The Hallmarks of Pseudoscience Spurious Similarities Refusal to Revise Explanation by Scenario Research by Literary Interpretation Eight Important Points Anecdotes do NOT make science Scientific language does NOT make science Bold statements do NOT make claims true Heresy does NOT equal correctness Eight Important Points Rumors do NOT equal reality Unexplained is NOT inexplicable Correlation does NOT mean causation Coincidence does NOT mean connection Always remember... “A wise man proportions his belief to the evidence.” David Hume