Karl Popper's main contribution to the philosophy of science concerns

Question

Passage A

Karl Popper's main contribution to the philosophy
of science concerns the power of negative evidence.
The fundamental point is simple: No number of white
swans, for example, can ever prove that all swans are
  (5)   white, but a single black swan disproves the hypothesis.
Popper gives this logical asymmetry between positive
and negative evidence hyperbolic application,
maintaining that positive evidence has no value as
evidence and that negative evidence is tantamount to
  (10)   disproof. Moreover, Popper takes the search for
negative evidence to be at the heart of scientific
research; that is, for Popper, scientific research
involves not only generating bold theories, but also
searching for evidence that would disprove them.
  (15)   Indeed, for him, a theory counts as scientific only if it
makes predictions that are testable in this way.

However, Popper's use of the logical asymmetry
does not adequately capture the actual situation
scientists face. If a theory deductively entails a false
  (20)   prediction, then the theory must be false as well. But
a scientific theory rarely entails predictions on its own.
When scientists actually derive a theory's predictions,
they almost always need diverse additional "auxiliary"
premises, which appeal to other theories, to the correct
  (25)   functioning of instrumentation, to the absence of
disturbing forces, etc. When a prediction fails, logic
indicates that at least one of the premises must be
false, but it does not indicate which one. When an
experiment does not work out as predicted, there is
  (30)   usually more than one possible explanation. Positive
evidence is never conclusive. But negative evidence
rarely is either.

Passage B

When the planet Uranus was discovered,
astronomers attempted to predict its orbit. They based
  (35)   their predictions on Newton's laws and auxiliary
assumptions about the mass of the sun and the masses,
orbits, and velocities of other planets. One of the
auxiliary assumptions was that no planets existed in
the vicinity of Uranus. When the astronomers made
  40)   their observations, they found that the orbit they had
predicted for Uranus was incorrect. One possible
explanation for the failure of their prediction was that
Newton's laws were incorrect. Another was that there
was an error in the auxiliary assumptions. The
  (45)   astronomers changed their assumptions about the
existence of other planets, concluding that there must
be another planet close enough to Uranus to produce
the observed orbit. Not long afterward, scientists
discovered the planet Neptune in the precise place it
  (50)   would have to be to bring their calculations into
alignment with their observations.

Later astronomers, again using Newton's laws,
predicted the orbit of Mercury. Once again, the
predictions were not borne out. They hypothesized the
  (55)   existence of another planet in the vicinity, which they
called Vulcan. However, Vulcan was never found, and
some scientists began to think that perhaps Newton's
laws were in error. Finally, when Einstein's general
theory of relativity was introduced, astronomers
  (60)   discovered that calculations based on that theory and
the old auxiliary assumptions predicted the observed
orbit of Mercury, leading to the rejection of Newton's
theory of gravity and to increased confidence in
Einstein's theory.    1 
 1. Which one of the following is a central topic of both passages?

(A) the logical asymmetry of positive and negative evidence
(B) the role of auxiliary assumptions in predicting planetary orbits
(C) the role of negative evidence in scientific research
(D) the proper technique for confirming a scientific theory
(E) the irrelevance of experimentation for disproving a scientific theory

2 
 2. Which one of the following is mentioned in passage A and illustrated in passage B?

(A) repudiating an experimental result
(B) revising a theory
(C) disproving a theory
(D) predicting a planet's orbit
(E) theories that are not testable by experiment

3 
 3. In passage B, which one of the following most clearly illustrates a disturbing force, as described in passage A (line 26)?

(A) Uranus
(B) the sun
(C) Neptune
(D) Mercury
(E) the moon

4 
 4. In saying that Popper gives a certain idea "hyperbolic application" (line 7), the author of passage A means to suggest that Popper

(A) extends the idea to cases in which it does not apply
(B) underestimates the significance of the idea
(C) commits a logical fallacy in reasoning about the idea
(D) draws too radical a conclusion from the idea
(E) exaggerates the idea's relevance to a particular theory

5 
 5. The author of passage A would be most likely to take which one of the following results mentioned in passage B as support for the claim made in the last sentence of passage A?

(A) the discovery of Uranus
(B) the initial failure of Newton's laws to correctly predict Uranus's orbit
(C) the ultimate failure of Newton's laws to correctly predict Mercury's orbit
(D) the failure to find Vulcan
(E) the success of Einstein's general theory of relativity at predicting Mercury's orbit

6 
 6. In passage B's description of the developments leading to the rejection of Newton's theory of gravity, which one of the following astronomical bodies plays a role most analogous to the black swan discussed in passage A?

(A) Mercury
(B) Uranus
(C) Neptune
(D) Venus
(E) the sun

7 
 7. It can be inferred that the author of passage B would be likely to be most skeptical of which one of the following ideas mentioned in passage A?

(A) Popper's main contribution to the philosophy of science concerned the power of negative evidence.
(B) Positive evidence plays no role in supporting a theory.
(C) Auxiliary premises are usually needed in order to derive predictions from a scientific theory.
(D) There is a logical asymmetry between positive and negative evidence.
(E) Scientific research involves generating bold theories and attempting to refine them.

8 
 8. Which one of the following scientific episodes is most analogous to the discovery of Neptune, as that episode is described in passage B?

(A) Galileo proposed that ocean tides are the result of Earth's motion in its orbit around the sun. But Galileo's theory of tides falsely predicted that there is only one high tide per day, when in fact there are two.
(B) By observing "variable stars"—stars that vary in brightness—in Andromeda, Edwin Hubble discovered that Andromeda is actually a galaxy in its own right. This enabled him to settle the debate about whether the Milky Way constitutes the entirety of the universe.
(C) Walter Alvarez postulated that an asteroid impact caused the extinction of the dinosaurs. He based this on observing high levels of the mineral iridium in certain rock core samples. Later evidence of a large impact crater was discovered in the Yucatan Peninsula that dates to the time of the dinosaur extinction.
(D) Bernard Rrunhcs discovered rocks that were magnetized in a direction opposite to that of the present-day magnetic field. He concluded that Earth's magnetic field must have been reversed at some point in the past.
(E) When a neutron decays into a proton and an electron, the combined energies of the two particles is less than the energy of the original neutron, in apparent contradiction of the law of conservation of energy. Wolfgang Pauli postulated that a third undetected particle is also created during the decay. The particle's existence was later confirmed.

Sajjad1994 · Answer

Explanation

6. In passage B's description of the developments leading to the rejection of Newton's theory of gravity, which one of the following astronomical bodies plays a role most analogous to the black swan discussed in passage A?

(A) Mercury
(B) Uranus
(C) Neptune
(D) Venus
(E) the sun

Explanation

The correct answer is  (A) .

In  Passage A , the black swan is used as an example of how a single piece of negative evidence can disprove a hypothesis. In  Passage B , the rejection of Newton's theory of gravity is similarly brought about by a single piece of evidence that contradicts its predictions.

In particular, the orbit of Mercury did not match the predictions of Newton's laws, even after astronomers hypothesized the existence of an unknown planet (Vulcan) to account for the discrepancy. However, when Einstein's theory of general relativity was introduced, it provided a new explanation for the orbit of Mercury that did not require the existence of Vulcan and was consistent with observations. This led to the rejection of Newton's theory of gravity and increased confidence in Einstein's theory.

Therefore, Mercury is the astronomical body that plays a role most analogous to the black swan in Passage A, as it provided a crucial piece of evidence that disproved a widely accepted theory and led to the development of a new and more accurate theory.

Answer: A

Sajjad1994 · Answer

Explanation

7. It can be inferred that the author of passage B would be likely to be most skeptical of which one of the following ideas mentioned in passage A?

Explanation

The author of passage B describes the process of scientific discovery, specifically in the case of predicting the orbits of Uranus and Mercury. In doing so, the author discusses the use of auxiliary assumptions and the need for scientists to consider multiple possible explanations when predictions fail.

In contrast, passage A focuses on the philosophical concept of the power of negative evidence, as articulated by Karl Popper. The author of passage A argues that Popper's use of the logical asymmetry between positive and negative evidence does not adequately capture the actual situation scientists face, as scientific theories rarely entail predictions on their own and often require auxiliary premises.

Given this, it can be inferred that the author of passage B would be most skeptical of Popper's assertion that positive evidence has no value as evidence (choice B) and his hyperbolic application of the power of negative evidence. The author of passage B would likely argue that auxiliary premises and multiple possible explanations must be taken into account when evaluating the strength of scientific evidence, rather than relying solely on the presence or absence of positive or negative evidence.

Therefore, the correct answer is B) Positive evidence plays no role in supporting a theory.

Answer: B

Sajjad1994 · Answer

Explanation

5. The author of passage A would be most likely to take which one of the following results mentioned in passage B as support for the claim made in the last sentence of passage A?

Explanation

The question is asking for a result from passage B that would serve as evidence for the claim that negative evidence is rarely conclusive.

A. No.  Passage B does not discuss the discovery of Uranus, only the difficulty predicting its orbit.

B.  Yes.   Newton’s laws accurately predicted the orbit of Neptune and it was the assumption that Neptune didn’t exist that made the prediction about Uranus inaccurate.

C. No.  This would be an effective use of negative evidence.

D. No.  Failure to find something is not negative evidence. Negative evidence is finding something that goes against a theory.

E. No.  The successful use of a theory is positive evidence, not negative evidence.

Answer: B

Sajjad1994 · Answer

Explanation

4. In saying that Popper gives a certain idea "hyperbolic application" (line 7), the author of passage A means to suggest that Popper

Explanation

The question is asking what the author thinks about Popper. The author accuses Popper of believing that positive evidence has no value as evidence and that negative evidence is disproof. The correct answer will be the statement that is best supported by evidence within the passage text.

A. No.  The author is arguing that Popper’s idea is too extreme because the reality is more complicated than Popper treats it.

B. No.  The author is arguing that Popper overestimates the value of negative evidence.

C. No.  The author is not arguing that the idea fails in all cases, just that Popper takes it to the extreme.

D.  Yes.   The author is accusing Popper of being too extreme.

E. No.  The author’s criticism is that the idea is too extreme, not that it doesn’t fit one particular theory.

Answer: D

Sajjad1994 · Answer

Explanation

3. In passage B, which one of the following most clearly illustrates a disturbing force, as described in passage A (line 26)?

Exlanation

Passage A mentions a disturbing force as something that would need to be lacking for a theory’s prediction to come true. The correct answer will be something in passage B that reflects this description.

A. No.  Uranus was the subject of the prediction, not an outside force.

B. No.  The Sun was the subject of an auxiliary assumption, not an outside force.

C.  Yes.   Neptune was an outside factor that was not included in the prediction’s original assumptions.

D. No.  Mercury was the subject of a prediction, not an outside force.

E. No.  Passage B never mentions the Moon.

Answer: C

Karl Popper's main contribution to the philosophy of science concerns

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Karl Popper's main contribution to the philosophy of science concerns

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