Read each of the following passages carefully and answer the questions that follow.
From ancient times, men have believed that, under certain peculiar circumstances, life could arise spontaneously: from the ooze of rivers could come eels and from the entrails of dead bulls, bees; worms from mud, and maggots from dead meat. This belief was held by Aristotle, Newton and Descartes, among many others, and apparently the great William Harvey too. The weight of centuries gradually disintegrated men's beliefs in the spontaneous origin of maggots and mice, but the doctrine of spontaneous generation clung tenaciously to the question of bacterial origin.
In association with Buffon, the Irish Jesuit priest John Needham declared that he could bring about at will the creation of living microbes in heat-sterilised broths, and presumably, in propitiation, theorised that God did not create living things directly but bade the earth and water to bring them forth. In his Dictionaire Philosophique, Voltaire reflected that it was odd to read of Father Needham's claim while atheists conversely should deny a Creator yet attribute to themselves the power of creating eels. But, wrote Thomas Huxley, 'The great tragedy of science— the slaying of a beautiful hypothesis by an ugly fact — which is so constantly being enacted under the eyes of philosophers, was played, almost immediately, for the benefit of Buffon and Needham.
The Italian Abbé Spallanzani did an experiment. He showed that a broth sealed from the air while boiling never develops bacterial growths and hence never decomposes. To Needham's objection that Spallanzani had ruined his broths and the air above them by excessive boiling, the Abbé replied by breaking the seals of his flasks. Air rushed in and bacterial growth began! But the essential conflict remained. Whatever Spallanzani and his followers did to remove seeds and contaminants was regarded by the spontaneous generationists as damaging to the 'vital force' from whence comes new life.
Thus, doubt remained, and into the controversy came the Titanic figure of Louis Pasteur. Believing that a solution to this problem was essential to the development of his theories concerning the role of bacteria in nature, Pasteur freely acknowledged the possibility that living bacteria very well might be arising anew from inanimate matter. To him, the research problem was largely a technical one: to repeat the work of those who claimed to have observed bacterial entry. For the one that contended that life did not enter from the outside, the proof had to go to the question of possible contamination. Pasteur worked logically. He found during the experiments that after prolonged boiling, a broth would ferment only when air was admitted to it. Therefore, he contended, either air contained a factor necessary for the spontaneous generation of life or viable germs were borne in by the air and seeded in the sterile nutrient broth. Pasteur designed ingenious flasks whose long S-shaped necks could be left open. Air was trapped in the sinuous glass tube. Broths boiled in these flask tubes remained sterile. When their necks were snapped to admit ordinary air, bacterial growth would then commence — but not in every case. An occasional flask would remain sterile presumably because the bacterial population of the air is unevenly distributed. The forces of spontaneous generation would not be so erratic. Continuous scepticism drove Pasteur almost to fanatical efforts to control the ingredients of his experiments to destroy the doubts of the most sceptical. He ranged from the mountain air of Montanvert, which he showed to be almost sterile, to those deep, clear wells whose waters had been rendered germfree by slow filtration through sandy soil. The latter discovery led to the familiar porcelain filters of the bacteriology laboratory. With pores small enough to exclude bacteria, solutions allowed to percolate through them could be reliably sterilised.
The argument raged on and soon spilled beyond the boundaries of science to become a burning religious and philosophical question of the day. For many, Pasteur's conclusions caused conflict because they seemed simultaneously to support the Biblical account of creation while denying a variety of other philosophical systems. The public was soon caught up in the crossfire of a vigorous series of public lectures and demonstrations by leading exponents of both views, novelists, clergymen, their adjuncts and friends. Perhaps the most famous of these evenings in the theatre — competing perhaps with a great debate between Huxley and Bishop Wiberforce for elegance of rhetoric — was Pasteur's public lecture at the Sorbonne on April 7, 1864. Having shown his audience the swan necked flasks containing sterile broths, he concluded, "And, therefore, gentlemen, I could point to that liquid and say to you, I have taken my drop of water from the immensity of creation, and I have taken it full of the elements appropriated to the development of inferior beings. And I wait, I watch, I question it! — begging it to recommence for me the beautiful spectacle of the first creation. But it is dumb, dumb since these experiments were begun several years ago; It is dumb because I have kept it from the only thing man does not know how to produce: from the germs that float in the air, from life, for life is a germ and a germ is life. Never will the doctrine of spontaneous generation recover from the mortal blow of this simple experiment." And it is not. Today these same flasks stand immutable: they are still free of microbial life.
It is an interesting fact that despite the ringing declaration of Pasteur, the issue did not die completely. And although far from healthy, it is not yet dead. In his fascinating biography of Pasteur, Rene Dubos has traced the later developments which saw new eruptions of the controversy, new technical progress and criticism, and new energetic figures in the breach of the battle such as Bastion, for, and the immortal Tyndall, against, the doctrine of spontaneous generation. There was also new 'sorrow' for Pasteur as he read years later, in 1877, the last jottings of the great physiologist Claude Bernard and saw in them the 'mystical' suggestion that yeast may arise from grape juice. Even at this late date, Pasteur was stirred to new experiments again to prove to the dead Bernard and his followers the correctness of his position.
It seems to me that spontaneous generation is not only a possibility, but a completely reasonable possibility which should never be relinquished from scientific thought. Before men knew of bacteria, they accepted the doctrine of spontaneous generation as the 'only reasonable alternative' to a belief in supernatural creation. But today, as we look for satisfaction at the downfall of the spontaneous generation hypothesis, we must not forget that science has rationally concluded that life once did originate on earth by spontaneous generation. It was really Pasteur's evidence against spontaneous generation that for the first time brought the whole difficult question of the origin of life before the scientific world. In the above controversy, what was unreasonable was the parade of men who claimed to have 'proved' or who resolutely 'believed in' spontaneous generation on the face of proof — not that spontaneous generation cannot occur — but that their work was shot through with experimental error. The acceptable evidence also makes it clear that spontaneous generation, if it does not occur, must obviously be a highly improbable event under present conditions. Logic tells us that science can only prove an event improbable: it can never prove it impossible — and Gamow has appropriately remarked that nobody is really certain what would happen if a hermetically sealed can were opened after a couple of million years. Modern science agrees that it was highly improbable for life to have arisen in the pre-Cambrian seas, but it concluded, nevertheless, that there it did occur. With this, I think, Pasteur would agree.
Aside from their theoretical implications, these researchers had the great practical result of putting bacteriology on a solid footing. It was now clear how precisely careful one had to be to avoid bacterial contamination in the laboratory. We now knew what 'sterile' meant and we knew that there could be no such thing as 'partial sterilization'. The discovery of bacteria high in the upper atmosphere, in the mud of the deep sea bottom, in the waters of hot springs, and in the Arctic glaciers established bacterial ubiquity as almost absolute. In recognition of this Lord Lister introduced aseptic technique into the practice of surgery. It was the revolution in technique alone that made possible modern bacteriology and the subsequent research connecting bacteria to phenomena of human concern, research, which today is more prodigious than ever. We are just beginning to understand the relationship of bacteria to certain human diseases, to soil chemistry, nutrition, and the phenomenon of antibiosis, wherein a product of one organism (e.g. penicillin) is detrimental to another.
It is not an exaggeration then to say that the emergence of the cell theory represents biology's most significant and fruitful advance. The realisation that all plants and animals are composed of cells which are essentially alike, that cells are all formed by the same fundamental division process, that the total organism is made up of activities and inter-relations of its individual cells, opened up horizons we have not even begun to approach. The cell is a microcosm of life, for in its origin, nature and continuity resides the entire problem of biology.
Needham's theory that 'God did not create living things directly' was posited as
Show Hint
- an attempt to support his assertion by religious doctrine.
- an attempt to placate his religious peers.
- an attempt at propitiating a possibly offended God or the religious psyche of the time.
- All of these.
The Correct Option is D
Solution and Explanation
It can be inferred from the passage that
Show Hint
- Huxley, Buffon and Needham were contemporaries.
- Buffon, Needham, Voltaire and Huxley were contemporaries.
- Voltaire wrote a treatise on Needham's claim.
- None of these
The Correct Option is B
Solution and Explanation
According to the passage,
Show Hint
- Pasteur's precursors in the field worked on the basis of spontaneous generation.
- unlike his predecessors, Pasteur worked on logical premises rather than arbitrary and spontaneous discoveries.
- Pasteur stood to benefit largely from the work of his predecessors.
- Pasteur developed the ideas set forth by Voltaire and Needham.
The Correct Option is B
Solution and Explanation
Pasteur began his work on the basis of the contention that
Show Hint
- either air contained a factor necessary for the spontaneous generation of life or viable germs were borne in by the air and seeded in the sterile nutrient broth.
- after prolonged boiling, a broth would ferment only when air was admitted to it.
- Both (1) and (2).
- Neither (1) nor (2).
The Correct Option is C
Solution and Explanation
The porcelain filters of the bacteriology laboratories owed their descent to
Show Hint
- Pasteur's homeland.
- the well water of Montanvert that had been rendered germ-free by slow filtration through sandy oil.
- Both (1) and (2).
- None of these.
The Correct Option is B
Solution and Explanation
What according to the passage was Pasteur's declaration to the world?
Show Hint
- Nobody could deny the work done by him.
- Science would forever be indebted to his experiments in bacteriology.
- The doctrine of spontaneous generation would never recover from the mortal blow dealt to it by his experiments.
- Those who refused to acknowledge his experiments would regret their scepticism.
The Correct Option is C
Solution and Explanation
What according to the writer, was the problem with the proponents of spontaneous generation?
Show Hint
- Their work had no scientific basis.
- Their work was ruined by experimental errors.
- Both (1) and (2).
- Neither (1) nor (2).
The Correct Option is C
Solution and Explanation
One of the results of the theoretical cross-fire regarding bacteriology was that
Show Hint
- partial sterilization as a possibility was ruled out.
- aseptic technique was introduced in surgery.
- the meaning of sterile was clear to all.
- All of these.
The Correct Option is D
Solution and Explanation
One of the reasons for the conflict caused by Pasteur's experiments was that
Show Hint
- they denied the existence of God as the creator.
- they seemed simultaneously to support the Biblical account of creation while denying a variety of other philosophical systems.
- academics and scientists refused to accept his theories.
- there were too many debates on the topic and this left the people confused.
The Correct Option is B
Solution and Explanation
According to the author,
Show Hint
- it is an exaggeration to say that cell theory represents biology's most significant and fruitful advance.
- Pasteur could not hold his own against the contenders.
- cell theory rendered null and void all the other bacteriological theories of the time.
- the emergence of the cell theory represents biology's most significant and fruitful advance.
The Correct Option is D
Solution and Explanation
Top Questions on Reading Comprehension
- Acrucial moderating factor in how people experience comparisons is self-esteem. Individuals with high self-esteem are more likely to interpret upward comparison as informative rather than threatening. They are more resilient in the face of others’ success and more likely to believe they can reach their own goals. In contrast, people with low self-esteem are more prone to interpret comparison as judgment, reinforcing negative self-views and triggering feelings of inadequacy.
This dynamic creates a self-reinforcing loop. People with high self-esteem are less vulnerable to upward comparison, which intensifies those doubts. Those with a secure sense of self are more likely to use comparison as a learning tool. The same external stimulus—a colleague’s achievements, a friend’s popularity—can have radically different effects depending on internal stability.
Self-esteem also influences how people choose their comparison targets. Research has found that individuals often engage in “selective comparison,” seeking out those who confirm their existing beliefs about themselves. This can become a subtle form of self-sabotage. Someone who feels unworthy may subconsciously seek out targets that reinforce that sense, perpetuating a narrative of inferiority. One of the most promising antidotes to social comparison is temporal comparison—evaluating oneself not against others, but against one’s own past. This method has been shown to increase motivation and satisfaction, especially when individuals can see concrete progress. Temporal comparison activates the same reward circuits as social comparison but avoids the threat systems associated with social ranking. It also reinforces agency: individuals focus on what they can control and improve rather than what others control. In therapeutic and coaching settings, temporal comparison is used to help clients build self-efficacy and track growth over time.
Moreover, people who focus on self-improvement rather than social dominance are less likely to fall into cycles of envy or self-pity. They can still use others as inspiration, but they do so without attaching their self-worth to the outcome. This is not to say they never compare—but that they focus on learning, rather than judgment. The most skilful approach to comparison may lie in eliminating it, but in reframing it as feedback. When we interpret comparison as information rather than a verdict, we can ask, “What can I learn from this?” This shift turns comparison into a growth tool. Teachers mentor their students, not as rivals. Psychologists emphasize that the key variable here is mindset.
A fixed mindset sees comparison as a threat. If someone else is better, it means we are worse. A growth mindset sees comparison as a map. If someone else has reached a certain level, it means the path exists. This reframing is not just a cognitive trick. It changes the emotional tone of comparison, making it more likely to inspire than to wound. Reframing also requires emotional regulation—the ability to notice an initial pang of envy or shame without reacting impulsively. With practice, individuals can learn to pause, reflect, and reinterpret their emotional responses. Over time, this builds resilience and self-trust, allowing comparison to become a learning tool rather than a cage.- XAT - 2026
- Verbal and Logical Ability
- Reading Comprehension
When people who are talking don’t share the same culture, knowledge, values, and assumptions, mutual understanding can be especially difficult. Such understanding is possible through the negotiation of meaning. To negotiate meaning with someone, you have to become aware of and respect both the differences in your backgrounds and when these differences are important. You need enough diversity of cultural and personal experience to be aware that divergent world views exist and what they might be like. You also need the flexibility in world view, and a generous tolerance for mistakes, as well as a talent for finding the right metaphor to communicate the relevant parts of unshared experiences or to highlight the shared experiences while demphasizing the others. Metaphorical imagination is a crucial skill in creating rapport and in communicating the nature of unshared experience. This skill consists, in large measure, of the ability to bend your world view and adjust the way you categorize your experiences. Problems of mutual understanding are not exotic; they arise in all extended conversations where understanding is important.
When it really counts, meaning is almost never communicated according to the CONDUIT metaphor, that is, where one person transmits a fixed, clear proposition to another by means of expressions in a common language, where both parties have all the relevant common knowledge, assumptions, values, etc. When the chips are down, meaning is negotiated: you slowly figure out what you have in common, what it is safe to talk about, how you can communicate unshared experience or create a shared vision. With enough flexibility in bending your world view and with luck and charity, you may achieve some mutual understanding.
Communication theories based on the CONDUIT metaphor turn from the pathetic to the evil when they are applied indiscriminately on a large scale, say, in government surveillance or computerized files. There, what is most crucial for real understanding is almost never included, and it is assumed that the words in the file have meaning in themselves—disembodied, objective, understandable meaning. When a society lives by the CONDUITmetaphor on a large scale, misunderstanding, persecution, and much worse are the likely products.- XAT - 2026
- Verbal and Logical Ability
- Reading Comprehension
Later, I realized that reviewing the history of nuclear physics served another purpose as well: It gave the lie to the naive belief that the physicists could have come together when nuclear fission was discovered (in Nazi Germany!) and agreed to keep the discovery a secret, thereby sparing humanity such a burden. No. Given the development of nuclear physics up to 1938, development that physicists throughout the world pursued in all innocence of any intention of finding the engine of a new weapon of mass destruction—only one of them, the remarkable Hungarian physicist Leo Szilard, took that possibility seriously—the discovery of nuclear fission was inevitable. To stop it, you would have had to stop physics. If German scientists hadn’t made the discovery when they did, French, American, Russian, Italian, or Danish scientists would have done so, almost certainly within days or weeks. They were all working at the same cutting edge, trying to understand the strange results of a simple experiment bombarding uranium with neutrons. Here was no Faustian bargain, as movie directors and other naifs still find it intellectually challenging to imagine. Here was no evil machinery that the noble scientists might hide from the problems and the generals. To the contrary, there was a high insight into how the world works, an energetic reaction, older than the earth, that science had finally devised the instruments and arrangements to coart forth. “Make it seem inevitable,” Louis Pasteur used to advise his students when they prepared to write up their discoveries. But it was. To wish that it might have been ignored or suppressed is barbarous. “Knowledge,” Niels Bohr once noted, “is itself the basis for civilization.” You cannot have the one without the other; the one depends upon the other. Nor can you have only benevolent knowledge; the scientific method doesn’t filter for benevolence. Knowledge has consequences, not always intended, not always comfortable, but always welcome. The earth revolves around the sun, not the sun around the earth. “It is a profound and necessary truth,” Robert Oppenheimer would say, “that the deep things in science are not found because they are useful; they are found because it was possible to find them.”
...Bohr proposed once that the goal of science is not universal truth. Rather, he argued, the modest but relentless goal of science is “the gradual removal of prejudices.” The discovery that the earth revolves around the sun has gradually removed the prejudice that the earth is the center of the universe. The discovery of microbes is gradually removing the prejudice that disease is a punishment from God. The discovery of evolution is gradually removing the prejudice that Homo sapiens is a separate and special creation.- XAT - 2026
- Verbal and Logical Ability
- Reading Comprehension
As the post–World War II generation of liberal democratic leaders forged new, highly successful domestic and international institutions and policies throughout the West, the weaknesses of liberal democracy that dominated the two decades after World War II faded from view. But they did not go away.
First, because liberal democracy restrains majorities, it slows the achievement of goals that majorities support. This generates frustration with institutional restraints, and an unacknowledged envy of authoritarian systems that can act quickly and decisively. China can build huge cities in the time it takes the United States to review the environmental impact of small highway projects. Liberal democracy requires more patience than many possess. Second, liberal democracy requires tolerance for minority views and ways of life to which many citizens are deeply opposed. It is natural to feel that if we consider certain views or ways of life to be odious, we should use public power to suppress them. In many such cases, liberal democracy restrains this impulse, a psychological burden that some will find unbearable.
This leads directly to the third inherent problem of liberal democracy—the distinction it requires us to make between civic identity and personal or group identity. For example, although we may consider certain religious views false and even dangerous, we must, for civic purposes, accept those who hold these views as our equals. They may freely express these views; they may organize to promote them; they may vote, and their votes are given the same weight as ours. The same goes for race, ethnicity, gender, and all the particularities that distinguish us from one another.
This requirement often goes against the grain of natural sentiments. We want the public sphere to reflect what we find most valuable about our private commitments. Liberal democracy prevents us from fully translating our personal identities into our public lives as citizens. This too is not always easy to bear. The quest for wholeness—for a political community, or even a world, that reflects our most important commitments—is a deep yearning to which liberal leaders can always appeal.
Nor is the fourth inherent difficulty of liberal democracy—the necessity of compromise—easy to bear. If what I want is good and true, why should I agree that public decisions must incorporate competing views? James Madison gives us the answer: in circumstances of liberty, diversity of views is inevitable, and unless those who agree with us form a majority so large as to be irresistible, the alternative to compromise is inaction, which is often more damaging, or oppression, which always is.- XAT - 2026
- Verbal and Logical Ability
- Reading Comprehension
Beware of the old newspapers
stacked
on that little three legged stool over there.
Don’t disturb them.
I know it for a fact
that snakes have spawned in between these sheets.
Don’t even look in that direction.
It’s not because of breeze
that their corners are fluttering.
It’s alive, that nest of newspapers.
new born snakes, coiling and uncurling,
are turning their heads to look at you.
That white corner has spread its hood.
A forked tongue
shoots out of its mouth.
Keep your eyes closed.
Get rid of the whole goddamn pile if you
want to
in the morning.- XAT - 2026
- Verbal and Logical Ability
- Reading Comprehension
Questions Asked in CAT exam
- In the set of consecutive odd numbers $\{1, 3, 5, \ldots, 57\}$, there is a number $k$ such that the sum of all the elements less than $k$ is equal to the sum of all the elements greater than $k$. Then, $k$ equals?
- CAT - 2025
- Number Systems
- The number of distinct pairs of integers $(x, y)$ satisfying the inequalities $x>y \ge 3$ and $x + y<14$ is:
- CAT - 2025
- Number Systems
For any natural number $k$, let $a_k = 3^k$. The smallest natural number $m$ for which \[ (a_1)^1 \times (a_2)^2 \times \dots \times (a_{20})^{20} \;<\; a_{21} \times a_{22} \times \dots \times a_{20+m} \] is:
- CAT - 2025
- Linear Inequalities
- The number of distinct integers $n$ for which $\log_{\left(\frac14\right)(n^2 - 7n + 11)>0$ is:}
- CAT - 2025
- Linear Inequalities
- If $a - 6b + 6c = 4$ and $6a + 3b - 3c = 50$, where $a, b$ and $c$ are real numbers, the value of $2a + 3b - 3c$ is:
- CAT - 2025
- Linear & Quadratic Equations