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Testing

In the twentieth century, philosopher Karl Popper introduced the idea that a hypothesis must be falsifiable; that is, it must be capable of being demonstrated wrong. A hypothesis must make specific predictions; (40) these predictions can be tested with concrete measurements to support or refute the hypothesis. For instance, Albert Einstein’s theory of gen­eral relativity makes a few specific predictions about the structure of space and flow of time, such as the prediction that light bends in a strong gravitational field, and the amount of bending depends in a pre-(45) cise way on the strength of the gravitational field. Observations made of a 1919 solar eclipse supported this hypothesis against other possi­ble hypotheses, such as Sir Isaac Newton’s theory of gravity, which did not make such a prediction. British astronomers used the eclipse to prove Einstein’s theory and therefore, eventually replaced Newton’s (50) theory.

Verification

Probably the most important aspect of scientific reasoning is verifi­cation. Verification is the process of determining whether the hypothesis is in accord with empirical evidence, and whether it will

(55) continue to be in accord with a more generally expanded body of evi­dence. Ideally, the experiments performed should be fully described so that anyone can reproduce them, and many scientists should inde­pendently verify every hypothesis. Results that can be obtained from experiments performed by many are termed reproducible and are

(60) given much greater weight in evaluating hypotheses than non-repro­ducible results.

Evaluation

Falsificationism argues that any hypothesis, no matter how respected or time-honored, must be discarded once it is contradicted by new reli-(65) able evidence. This is, of course, an oversimplification, since individ­ual scientists inevitably hold on to their pet theory long after contrary evidence has been found. This is not always a bad thing. Any theory can be made to correspond to the facts, simply by making a few adjust­ments—called “auxiliary hypothesis”—so as to bring it into corre-(70) spondence with the accepted observations. The choice of when to reject one theory and accept another is inevitably up to the individual scientist, rather than some methodical law.

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Hence all scientific knowledge is always in a state of flux, for at any time new evidence could be present[ed] that contradicts long-held

(75) hypotheses.

The experiments that reject a hypothesis should be performed by many different scientists to guard against bias, mistake, misunderstand­ing, and fraud. Scientific journals use a process of peer review, in which scientists submit their results to a panel of fellow scientists (who may or

(80) may not know the identity of the writer) for evaluation. Peer review may well have turned up problems and led to a closer examination of exper­imental evidence for many scientists. Much embarrassment, and wasted effort worldwide, has been avoided by objective peer review, in addition to continuing the use and proving the necessity of the scientific method.

391. Which step in the process of scientific method do lines 63–72 speak of?

a. operational definition

b. verification

c. evaluation

d. phenomenon

e. hypothesizing

392. What is the tone of this passage?

a. enigmatic

b. apathetic

c. abstruse

d. instructive

e. revealing

393. In line 63 the word falsificationism most nearly means

a. validation.

b. qualification.

c. confirmation.

d. facilitation.

e. refutation.

394. Which statement is FALSE?

a. Reproducible results can be obtained by experiments performed by a variety of scientists.

b. An auxiliary hypothesis can be made to correspond to the facts.

c. Einstein’s theory of relativity makes space and time predictions.

d. Peer review is usually not a valuable tool for scientists.

e. Experiments are a necessary element in the scientific method.

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395. According to the passage, which is true of a hypothesis?

a. It is not a necessary process in the scientific method.

b. It cannot be discarded by a competing theory.

c. It is a guess.

d. It can make a broad and general prediction.

e. It is always considered auxiliary.

396. What is the best title for this passage?

a. The Theory of Relativity

b. The Scientific Method: A Step-by-Step Process

c. The Tw o Stages of Proving Theories

d. How to Form a Hypotheses

e. Evaluating Data with the Scientific Method

397. What is meant by the term operational definition in line 28 of the passage?

a. a scientific law

b. a theory

c. a clear definition [of a measurement]

d. scientific method

e. hypothesis

398. What do lines 37–48 of the passage indicate?

a. The theory of general relativity is a hypothesis.

b. Karl Popper proved the theory of relativity to be incorrect.

c. Einstein was the father of the scientific method.

d. Space and the flow of time theories are still in a state of flux.

e. Sir Isaac Newton’s theory of gravity disproved Einstein’s theory.

399. Which is NOT a step used in the process of scientific method?

a. observation

b. simplification

c. evaluation

d. verification

e. hypothesize

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