WHAT IS THE NATURE OF SCIENCE?

WHAT IS THE NATURE OF SCIENCE? Please read the complete article which is posted at my website for you There is also a PPT summary posted at my website for you Please use them for your Exam 1 review

THIS IS THE SCIENTIFIC WORLD VIEW The Universe Is Understandable. The Universe Is a Vast Single System In Which the Basic Rules Are Everywhere the Same. Scientific Ideas Are Subject To Change. Scientific Knowledge Is Durable. Science Cannot Provide Complete Answers to All Questions.

WHAT IS THE NATURE OF SCIENTIFIC INQUIRY? Certain features of science make it distinctive as a means of understanding the world/universe Those features are especially characteristic of the work of professional scientists, but anyone can use them to think scientifically about many aspects of everyday life

Science Demands Evidence The validity of scientific claims is settled by referring to observations of phenomena Therefore, scientists concentrate on getting accurate data

THE SCIENTIFIC METHOD Observe and describe a phenomenon or group of phenomena Formulate hypotheses to explain the phenomena; hypotheses often take the form of a proposed causal mechanism or mathematical relationship Use the hypotheses to predict the existence or actions of other phenomena, or to predict quantitatively the results of new observations Perform additional data collection or repeat experimental tests of the predictions by several independent experimenters using properly performed techniques or experiments

THE SCIENTIFIC METHOD Observations/Data ➔ Hypotheses ➔ Hypothesis Testing ➔ Models ➔ Laws ➔ Theories At some point in time, each stage must be reported to the larger scientific community by presentations or publications

THE SCIENTIFIC METHOD The scientific method does not allow any hypothesis to be proven true Hypotheses can be disproven, in which case those hypothesis are rejected as false A hypothesis which withstands a test designed to falsify it establishes a level of probability that the hypothesis accurately explains data and can be used for further predictions, subject to further tests

SCIENTIFIC LAWS AND THEORIES A Scientific Theory is an explanation of a set or system of related observations or events based upon proven hypotheses and verified multiple times by detached groups of unbiased researchers (One scientist cannot establish a theory; s/he can only create hypotheses) A few scientists are honored for founding a theory later in history: Newton, Dalton, Darwin, Einstein

SCIENTIFIC LAWS AND THEORIES As a result of our confidence in the Scientific Method, both scientific laws and broader scientific theories are accepted to be “true” (accurate) by the scientific community as a whole A scientific law or a scientific theory is used to make predictions of events or relationships among data sets

SCIENTIFIC LAWS AND THEORIES The biggest difference between a law and a theory is that a theory is much more complex and dynamic A law governs a single action or situation, whereas a theory explains an entire group of related phenomena (Mendel’s Laws of Heredity versus Darwin’s Theory of Evolution by Natural Selection) [Note: Evolution is a Fact; Darwin’s Theory is the scientifically accepted explanation for the fact(s) and mechanisms of evolution.]

SCIENTIFIC LAWS AND THEORIES Genuine scientific theories must be falsifiable by applying the scientific method (data collection and hypothesis testing) If one cannot imagine a specific investigation or experiment, based on predictions from the theory, leading to results which can further verify or refute the predictions, then the theory, as an explanation, is not scientific

SCIENTIFIC LAWS AND THEORIES When the scientific community accepts a Law or Theory, it represents the best understanding of the explanations for the properties of a given system at that point in time A Scientific Theory represents our best understanding of the “truth” about some aspect of the universe, even though it is not proven as absolute and is still understood to be subject to future revision, or even to rejection

THE EXPERIMENTAL METHOD The Experimental Method is usually considered the most scientific of all methods, the “method of choice” The main problem with all other non-experimental methods is investigators have less control over the situation and its components The Experimental Method exerts the most control on data collection and interpretation

THE EXPERIMENTAL METHOD An experiment is a study of cause and effect It differs from non-experimental methods in that it involves the deliberate manipulation of one variable, while trying to keep all other variables constant Experiments must be properly designed and include controls

HYPOTHESIS GENERATION The use of logic and the close examination of evidence are necessary but not usually sufficient for the advancement of science Scientific concepts do not emerge automatically from data or from any amount of analysis alone Inventing hypotheses or theories to imagine how the world works and then figuring out how the hypotheses can be put to the test of reality is a creative thought process

SCIENCE EXPLAINS AND PREDICTS Scientists construct explanations for observations that are consistent with currently accepted scientific principles Such explanations—theories—may be either sweeping or restricted, but they must be logically sound and incorporate a significant body of scientifically valid observations The credibility of scientific theories often comes from their ability to predict relationships among phenomena that previously seemed unrelated

SCIENCE EXPLAINS AND PREDICTS It is not enough for scientific theories to explain the observations that are already known Theories should also explain additional observations that were not used in formulating the theories in the first place; that is, theories should have predictive power

SCIENTISTS TRY TO IDENTIFY AND TO AVOID BIAS When faced with a claim that something is true, scientists respond by asking what evidence supports it But scientific evidence can be biased in how the data are interpreted, recorded or reported, or even in the choice of what data are considered in the first place A scientist’s nationality, culture, gender, ethnic origin, age, political convictions, etc., may incline him or her to look for or emphasize one kind of evidence or interpretation over another

SCIENCE IS NOT AUTHORITARIAN In science, it is appropriate to turn to knowledgeable sources of information and opinion, usually specialists in relevant disciplines But respected authorities have been wrong many times in the history of science Aristotle

SCIENCE IS SELF CORRECTING AND PROGRESSIVE In the short run, new ideas that do not agree well with mainstream ideas may encounter vigorous criticism, and scientists investigating such ideas may have difficulty obtaining support for their research Challenging new ideas is the legitimate business of science in building valid knowledge

SCIENCE IS SELF CORRECTING AND PROGRESSIVE SF Author Sir Arthur C. Clarke’s First Law: “When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.”

SCIENCE AS A WAY OF KNOWING The Universe Is Understandable The Universe Is a Vast Single System In Which the Basic Rules Are Everywhere the Same Scientific Ideas Are Subject To Change Scientific Knowledge Is Durable Science Cannot Provide Complete Answers to All Questions Scientific ideas are developed by particular ways of observing, thinking, experimenting, and validating Observations/Data ➔ Hypotheses ➔ Hypothesis Testing ➔ Models ➔ Laws ➔ Theories

Principles and Processes of Evolution For the rest of the semester, we will examine the fact(s) of Evolution and the evidence that supports Darwin’s/Biology’s Theory of Evolution by Natural Selection We will also expose “Intelligent Design” as an unsatisfactory alternative scientific explanation of causation in Biology

WHAT IS THE NATURE OF SCIENCE? END

Hypothesis Testing