3 Definition of Science “Science is the search for truth” – NO! “Science is what scientists do” (or what is done at scientific institutions) – NO!Science is a process that relies on a strict investigative method for understanding the world around us by evaluating evidence through reasonThe scientific method is the process for evaluating evidence
4 The Scientific MethodObservations are used to develop testable predictions called hypothesesAdditional observations or experiments are used to examine the validity of a hypothesis (falsification)If necessary, hypotheses are restated in response to discrepancies after testingA hypothesis that has withstood rigorous testing is considered a theorySeveral related theories may constitute a scientific law
5 Tools of the Scientific Method LogicDeductive (general observations → specific conclusions)All men are mortal (premise 1)Socrates is a man (premise 2)Socrates is mortal (conclusion)Inductive (specific observations → general conclusions)e.g., specific symptoms are used to identify an illness
6 Tools of the Scientific Method The controlled experimentAll variables, except for the one being investigated, are kept constantFalsification is a critical step where the investigator (and others) try to show that the hypothesis is falseHypotheses can be disproved but never proven (someday another observation may contradict the hypothesis)
7 Tools of the Scientific Method Mathematical modelsThe language of science should be very precise (no additional “interpretations” are permitted)Mathematical expressions are the most precise language
8 Peer Review Scientific discoveries should be original The scientist should be free of bias that would influence interpretation of resultsConclusions should stand on their own merit and not need support from outside factors (e.g., social, ethnic, religious, personal desires)Scientific statements are not accepted on faith and must withstand close scrutiny including falsification attemptsScientific knowledge, including methodology, should be freely available to the publicThe language used should be precise and unambiguous
9 Key Points Science is conducted by formulating and testing hypotheses Scientific advancement depends on rejecting hypotheses (acceptance is always conditional)If a hypothesis cannot be tested, the scientific method cannot be employed and the hypothesis lies outside the realm of science.