Essayist: Common sense, which is always progressing, is nothing but a collection of theories that have been tested over time and found useful. When alternative theories that prove even more useful are developed, they gradually take the place of theories already embodied in common sense. This causes common sense to progress, but, because it absorbs new theories slowly, it always contains some obsolete theories.
Summary
Common sense is always progressing.
Common sense is a collection of theories that have been tensed and found useful over time.
Alternative theories that are even more useful gradually replace the theories that are common sense.
This replacement happens slowly, so common sense always contains some obsolete theories.
Notable Valid Inferences
In common sense, there are always at least some theories that have more useful alternatives.
A
At least some new theories that have not yet been found to be more useful than any theory currently part of common sense will never be absorbed into the body of common sense.
This could be false. The stimulus discusses theories that are already developed and proven to be more useful. Further, the stimulus doesn’t discuss which theories will never be absorbed into common sense.
B
Of the useful theories within the body of common sense, the older ones are generally less useful than the newer ones.
This could be false. The stimulus does not give any relationship between age of theory and usefulness.
C
The frequency with which new theories are generated prevents their rapid absorption into the body of common sense.
This could be false. The stimulus just says that common sense absorbs new theories slowly; we don’t know the reason for this slow progress.
D
Each theory within the body of common sense is eventually replaced with a new theory that is more useful.
This could be false. We know that some theories are eventually replaced; we don’t know that each theory will be replaced.
E
At least some theories that have been tested over time and found useful are less useful than some other theories that have not been fully absorbed into the body of common sense.
This must be true. Progress is slow, so it takes time for alternative theories that have been proven to be more useful to be absorbed into common sense. Until these alternatives are absorbed into common sense, the theories in common sense are less useful than the alternatives.