LSAT Reading : Inferences About Passage Content in Science Passages

Study concepts, example questions & explanations for LSAT Reading

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Example Questions

Example Question #11 : Extrapolating From Science Passages

Adapted from Are the Planets Inhabited? by E. Walter Maunder (1913)

The first thought that men had concerning the heavenly bodies was an obvious one: they were lights. There was a greater light to rule the day, a lesser light to rule the night, and there were the stars also.

In those days there seemed an immense difference between the earth upon which men stood and the bright objects that shone down upon it from the heavens above. The earth seemed to be vast, dark, and motionless; the celestial lights seemed to be small, and moved and shone. The earth was then regarded as the fixed center of the universe, but the Copernican theory has since deprived it of this pride of place. Yet from another point of view, the new conception of its position involves a promotion, since the earth itself is now regarded as a heavenly body of the same order as some of those that shine down upon us. It is amongst them, and it too moves and shines—shines, as some of them do, by reflecting the light of the sun. Could we transport ourselves to a neighboring world, the earth would seem a star, not distinguishable in kind from the rest.

But as men realized this, they began to ask, “Since this world from a distant standpoint must appear as a star, would not a star, if we could get near enough to it, show itself also as a world? This world teems with life; above all, it is the home of human life. Men and women, gifted with feeling, intelligence, and character, look upward from its surface and watch the shining members of the heavenly host. Are none of these the home of beings gifted with like powers, who watch in their turn the movements of that shining point that is our world?”

This is the meaning of the controversy on the Plurality of Worlds which excited so much interest some sixty years ago, and has been with us more or less ever since. It is the desire to recognize the presence in the orbs around us of beings like ourselves, possessed of personality and intelligence, lodged in an organic body.

This is what is meant when we speak of a world being “inhabited.” It would not, for example, at all content us if we could ascertain that Jupiter was covered by a shoreless ocean, rich in every variety of fish, or that the hard rocks of the Moon were delicately veiled by lichens. Just as no richness of vegetation and no fullness and complexity of animal life would justify an explorer in describing some land that he had discovered as being “inhabited” if no men were there, so we cannot rightly speak of any other world as being “inhabited” if it is not the home of intelligent life. 

On the other hand, of necessity we are precluded from extending our inquiry to the case of disembodied intelligences, if such be conceived possible. All created existences must be conditioned, but if we have no knowledge of what those conditions may be, or means for attaining such knowledge, we cannot discuss them. Nothing can be affirmed, nothing denied, concerning the possibility of intelligences existing on the Moon or even in the Sun if we are unable to ascertain under what limitations those particular intelligences subsist.

The only beings, then, the presence of which would justify us in regarding another world as “inhabited” are such as would justify us in applying that term to a part of our own world. They must possess intelligence and consciousness on the one hand; on the other, they must likewise have corporeal form. True, the form might be imagined as different from that we possess, but, as with ourselves, the intelligent spirit must be lodged in and expressed by a living material body. Our inquiry is thus rendered a physical one; it is the necessities of the living body that must guide us in it; a world unsuited for living organisms is not, in the sense of this enquiry, a “habitable” world.

Which of the following CANNOT be inferred from the passage?

Possible Answers:

Some inhabited world could be the home of non-intelligent beings.

Some uninhabited world could be the home of non-intelligent beings.

No uninhabited world is the home of intelligent beings.

Every inhabited world is the home of intelligent beings.

Some uninhabited world could be the home of intelligent beings.

Correct answer:

No uninhabited world is the home of intelligent beings.


The presence of intelligent beings is a necessary, but not sufficient, condition for a world to be inhabited; however, the passage also implies that the presence of intelligent beings on an inhabited world does not necessarily imply a lack of unintelligent ones as well. While this is most strongly suggested by the description of terrestrial explorers needing to find human beings in addition to plant and animal life, it is not precluded by the logical structure of the argument. The presence of intelligent life does not necessarily exclude the presence of non-intelligent life (A does not imply not-B), even if there is nothing in the passage that suggests that intelligent life requires non-intelligent life.

Example Question #161 : Psat Critical Reading

Adapted from "Recent Views as to Direct Action of Light on the Colors of Flowers and Fruits" in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)

The theory that the brilliant colors of flowers and fruits is due to the direct action of light has been supported by a recent writer by examples taken from the arctic instead of from the tropical flora. In the arctic regions, vegetation is excessively rapid during the short summer, and this is held to be due to the continuous action of light throughout the long summer days. "The further we advance towards the north, the more the leaves of plants increase in size as if to absorb a greater proportion of the solar rays. M. Grisebach says that during a journey in Norway he observed that the majority of deciduous trees had already, at the 60th degree of latitude, larger leaves than in Germany, while M. Ch. Martins has made a similar observation as regards the leguminous plants cultivated in Lapland.” The same writer goes on to say that all the seeds of cultivated plants acquire a deeper color the further north they are grown, white haricots becoming brown or black, and white wheat becoming brown, while the green color of all vegetation becomes more intense. The flowers also are similarly changed: those which are white or yellow in central Europe becoming red or orange in Norway. This is what occurs in the Alpine flora, and the cause is said to be the same in both—the greater intensity of the sunlight. In the one the light is more persistent, in the other more intense because it traverses a less thickness of atmosphere.

Admitting the facts as above stated to be in themselves correct, they do not by any means establish the theory founded on them; and it is curious that Grisebach, who has been quoted by this writer for the fact of the increased size of the foliage, gives a totally different explanation of the more vivid colors of Arctic flowers. He says, “We see flowers become larger and more richly colored in proportion as, by the increasing length of winter, insects become rarer, and their cooperation in the act of fecundation is exposed to more uncertain chances.” (Vegetation du Globe, col. i. p. 61—French translation.) This is the theory here adopted to explain the colors of Alpine plants, and we believe there are many facts that will show it to be the preferable one. The statement that the white and yellow flowers of temperate Europe become red or golden in the Arctic regions must we think be incorrect. By roughly tabulating the colors of the plants given by Sir Joseph Hooker as permanently Arctic, we find among fifty species with more or less conspicuous flowers, twenty-five white, twelve yellow, eight purple or blue, three lilac, and two red or pink; showing a very similar proportion of white and yellow flowers to what obtains further south.

This passage is taken from a longer work. Based on what you have read, which of the following would you most expect to find in the paragraphs immediately following those in the passage?

Possible Answers:

Further consideration of the theory of the writer quoted in the first paragraph

Praise of the useful nature of Hooker’s research

A summary of a paper the author wishes to publish on the topic being discussed

A discussion of the historical uses of alpine plants

More evidence as to why Grisebach’s theory is the correct one

Correct answer:

More evidence as to why Grisebach’s theory is the correct one


In the concluding sentences of the passage, the author is asserting that Grisebach's interpretation is the correct one, not that of the "recent writer" quoted in the first paragraph. The author is also bringing up evidence (Joseph Hooker's enumerated observations) to prove his point. One could thus reasonably expect to encounter "more evidence as to why Grisebach’s theory is the correct one" if one read on further in the larger text of which this passage is a small part.

Example Question #1 : Inferences About Passage Content In Science Passages

Adapted from On the Origin of Species by Charles Darwin (1859)

The many slight differences which appear in the offspring from the same parents, or which it may be presumed have thus arisen, from being observed in the individuals of the same species inhabiting the same confined locality, may be called individual differences. No one supposes that all the individuals of the same species are cast in the same actual mold. These individual differences are of the highest importance for us, for they are often inherited, as must be familiar to every one; and they thus afford materials for natural selection to act on and accumulate, in the same manner as man accumulates in any given direction individual differences in his domesticated productions. These individual differences generally affect what naturalists consider unimportant parts; but I could show, by a long catalogue of facts, that parts which must be called important, whether viewed under a physiological or classificatory point of view, sometimes vary in the individuals of the same species. I am convinced that the most experienced naturalist would be surprised at the number of the cases of variability, even in important parts of structure, which he could collect on good authority, as I have collected, during a course of years. It should be remembered that systematists are far from being pleased at finding variability in important characters, and that there are not many men who will laboriously examine internal and important organs, and compare them in many specimens of the same species. It would never have been expected that the branching of the main nerves close to the great central ganglion of an insect would have been variable in the same species; it might have been thought that changes of this nature could have been effected only by slow degrees; yet Sir J. Lubbock has shown a degree of variability in these main nerves in Coccus, which may almost be compared to the irregular branching of the stem of a tree. This philosophical naturalist, I may add, has also shown that the muscles in the larvæ of certain insects are far from uniform. Authors sometimes argue in a circle when they state that important organs never vary; for these same authors practically rank those parts as important (as some few naturalists have honestly confessed) which do not vary; and, under this point of view, no instance will ever be found of an important part varying; but under any other point of view many instances assuredly can be given.

It can be inferred from the passage that "Sir J. Lubbock" is which of the following?

Possible Answers:

The author's lifelong friend and partner

A well-known researcher whose work has touched on the variability of animal organs

A well-respected member of the House of Lords

A prominent opponent of the author in scientific circles

A noted professor of science at an eminent university

Correct answer:

A well-known researcher whose work has touched on the variability of animal organs


The reference to "Sir J. Lubbock" is made only passing, but is used to support the author's overall claims about the variability of organs within species. Lubbock has found variation in the nerves of "Coccus." Without any other information, the only thing that can be inferred is that Lubbock has done scientific research which is both in league with the author's argument and, from the casual reference, somewhat widely read. There is no specific mention of Lubbock's position at a university, nor to his personal or professional relationship to the author.

Example Question #3 : Inferences About Passage Content In Science Passages

Passage adapted from Leon Gambetta's Educating the Peasantry (1869)

(1) We have received a classical or scientific education— even the imperfect one of our day. (3) We have learned to read our history, to speak our language, while (a cruel thing to say) so many of our countrymen can only babble! Ah! (4) That peasant, bound as he is to the tillage of the soil, who bravely carries the burden of his day, with no other consolation than that of leaving to his children the paternal fields, perhaps increased an acre in extent; all his passions, joys, and fears concentrated in the fate of his patrimony. (5) Of the external world, of the society in which he lives, he apprehends only legends and rumors. (6) He is the prey of the cunning and fraudulent. (7) He strikes, without knowing it, the bosom of the revolution, his benefactress… (8) It is to the peasantry, then, that we must address ourselves. (9) We must raise and instruct them… Enlightened and free peasants who are able to represent themselves… should be a tribute rendered to the progress of the civilization of the masses.

(10) …Progress will be denied us as long as the French democracy fail to demonstrate that if we would remake our country, if we would bring back her grandeur, her power, and her genius it is of vital interest to her superior classes to elevate and emancipate this people of workers, who hold in reserve a force still virgin but able to develop inexhaustible treasures of activity and aptitude. (11) We must learn and then teach the peasant what he owes to Society and what he has the right to ask of her.

(12) On the day when it shall be well understood that we have no grander or more pressing work; that we should put aside and postpone all other reforms: that we have but one task— the Instruction of the people, the diffusion of education, the encouragement of science— on that day a great step will have been taken in your regeneration. (13) But our action needs to be a double one, that it may bear upon the body as well as the wind. (14) To be exact, each man should be intelligent, trained not only to think, read, and reason, but made able to act and fight. (15) Everywhere beside the teacher we should place the gymnast and the soldier, to the end that our children, our soldiers, our fellow citizens, may be able to hold a sword, to carry a gun on a long march, to sleep under the canopy of the stars, to support valiantly all the hardships demanded of a patriot. (16) We must push to the front education. (17) Otherwise we only make a success of letters, but do not create a bulwark of patriots...

Who is most likely the intended audience of this passage?

Possible Answers:

The peasants 

Those opposing revolution


Overseas acquaintances 

Correct answer:



The likely intended audience of this passage are fellow reformers, as indicated by Gambetta's emphasis in paragraph three (beginning with Sentence 12) on education as the most pressing reform. 

The audience of the passage is presumably not the peasants, who, according to the author, "can only babble" without education (although the author does note that they "must address themselves" to the peasants). The intended audience is also not those opposing revolution, as Gambetta clearly seeks to further the cause of the revolution ("He strikes, without knowing it, the bosom of the revolution, his benefactress…"). The author makes no reference to overseas acquaintances.

Example Question #1 : Inferences About Passage Content In Science Passages

"Darwin and Wallace" (2016)

Alfred Russel Wallace developed what he termed “the tendency of varieties to depart from the original type” while on an extended research trip in Borneo. During earlier research in the Amazon basin, Wallace had observed that certain, highly similar species were often separated by a small distance, but some type of significant geographical barrier. Although he was halfway around the world, Wallace was keeping in touch with fellow scientists in his native Britain, including Charles Darwin, who was most notable at that time for a large book on barnacles and his trip around the world on the HMS Beagle over a decade and a half earlier.

When Wallace sent Darwin a letter in February of 1858, Wallace’s intention was merely to ask if his findings in Malaysia were consistent with Darwin’s private theorizing about the development of species. Darwin received the letter in June, and was astonished at what he read from Wallace. He fired off a letter to Charles Lyell, head of the prestigious scientific organization the Linnean Society. Lyell had previously expressed concern that Darwin’s long gestating theory of natural selection would be preempted by another researcher, expressing a strong likelihood it would be Wallace.

The custom among scientists at the time called for the first person to publish a theory to be given credit for it. Wallace was well on his way to publishing his own work, largely in the form of the letter he had sent Darwin. Lyell, who had been hearing about Darwin’s theory for fifteen years, believed that both men should receive some credit. With his position of authority at the Linnean Society, Lyell arranged to have a joint paper read at the last meeting before their summer break in 1858, which took place on the first of July. The meeting was relatively well attended for the time, with over thirty people in the audience, including two foreigners. The vast majority of them were there to hear a eulogy for Robert Brown, the Scottish botanist and former president of the Society, who had passed away in early June.

Neither Alfred Russell Wallace nor Charles Darwin were present at the meeting. Wallace was still in Southeast Asia, totally unaware that the joint paper was being presented, only being informed by a letter after the meeting. Darwin was in his native Kent, far away from London, burying his recently deceased baby son, Charles Waring Darwin, who had succumbed to scarlet fever just three days previously. Darwin gave Lyell and fellow scientist Robert Hooker Wallace’s letter, a letter he had written to the American researcher Asa Gray, and an essay he had written in 1844. He then told Lyell and Hooker that he was unable to attend.

Little was made of the joint reading. Only a few small reviews were made, none of which either greatly lauded or fiercely criticized the theory of natural selection. After this, Darwin left his home with his family, seeking to get away from the disease that killed his youngest child, and began a large book on the theory. Wallace kept traveling across the Malay Archipelago, finding new evidence for the theory everywhere he went.

Charles Darwin’s name would become indelibly linked with natural selection; in particular, its subsequent overarching idea of the evolution of human beings due to the big book he was writing, On the Origin of Species. Its publication in 1859 would revolutionize how scientists thought about natural history, biology, and even science’s relation to religion. Darwin would often retreat from public scrutiny and engagement. In his stead, it was often Alfred Russell Wallace, who had returned to England in 1862, defending what became known as “Darwin’s theory.” Wallace’s significant contribution to natural selection was recognized by scientists, but rarely by the public. Nonetheless, from prompting the initial publication of the idea to staunchly fighting for it, Alfred Russell Wallace was key to the development of evolution.

Based on the information provided in the passage, it can be inferred that Robert Brown:

Possible Answers:

was very well respected in the scientific community.

did not approve of Alfred Russell Wallace's trip to Malaysia.

was a mentor of Charles Darwin during Darwin's early career.

would not have approved of the theory of natural selection.

Correct answer:

was very well respected in the scientific community.


The information given in the passage about Robert Brown is that he was memorialized by the Linnean Society as a former president and respected botanist. With nothing else being said about Brown in the passage, the only inference that can be drawn is that Robert Brown was well respected by the scientific community.

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