Models from Leidong Zhang
Selective sample
The sample is randomly selected and is representative of the general group
Quantity of the sample, are the respondents representative, changing scope
To point out that the current sample is not randomly selected and could not represent the general group or that the survey only special groups of subjects while many people have been ignored
The author implies that the sample studied in the survey could present the general group, but the author consider only
Although the sub-group studied do constitute a significant part of the general group, many other sub-groups are excluded from the study.
The conditions situation of other sub-group might be quite different.
Without ruling out the above possibility, the author could not make any general conclusion about that the general population merely based on the selective sub-group.
Quantity of the sample
The sample size is insufficient to be statistically representative.
The quantity of the sample is sufficient to be representative.
To point out the current sample is not sufficient is size, and might not represent all the other sub-group.
The fact cited by the author could hardly illustrate the assumption that
The sample studied might be special cases and is too limited to be representative.
We cannot accept the authors implication that before more statistic data about are provided.
Do the statistics make any difference?
The purpose of the survey is insignificant in supporting the final conclusion
To point out that the result of the study could not give strong and sufficient support to the finial conclusion or even has nothing to do with the conclusion
The information provided by the author is in sufficient for illustrating the conclusion or assumption
The survey only studies the situation of some special cases
However, many more critical cases were ignored in the survey.
To evaluate the argument, we need the author to provide more information about the ignored cases and more information about other subjects
Lacking further studies on these important issues, the author could not hastily conclude that merely based on the insignificant study.
What questions were asked in the survey?
The question asked in the survey is not directly related to the final conclusion or the question itself may have some misleading effects.
Another flaw is the question asked in the survey about
Merely this question could not lend strong support to the authors conclusion that
The result cited above could hardly support the conclusion before the author could provide substantial evidence to illustrate that
Who conducted the survey
The institution who conducted the survey may have vested interest in the result, or it may affect the reliability of the result.
The institution should be neutral and have not vested interest in the result.
The reliability of the survey is also open to doubt due to the organization who conducted the survey.
The organization has vested interest in the final result which was based on the result of the survey and thus might distort the actual answer of the respondents
The author should cited a conclusion form a survey conducted by an independent constitution to convince us that the assumption
When was the survey conducted?
The survey was conducted in a special period, or was conducted a long time ago; the result of the survey could not represent the general situation
There were no fundamental change occurred during the period after the survey conducted.
The effectiveness of the survey cited as main evidence is open to doubt.
The survey was conducted, thus may not reflect the current situation accurately
The author should provide evidence that peoples opinion toward has not changed greatly during the past time.
A more recent survey, if necessary at all, should be provided to sufficiently illustrate the assumption that
Are the respondents forthright when answering the questions
The respondents may not express their actual opinion feeling or situation due to the circumstance which the survey was conducted.
To point out that some setting of the survey might be improper to obtain the true information from the respondents or the respondents might be unwilling to tell the truth for some reason. Validity and reliability
The reliability of the respondents answers is not sufficiently justified
There is possibility that the respondents may not tell the truth about for the reason that
Under such circumstance, it is almost impossible to expect the respondents to provide accurate information about
Are the respondents representative?
Same with the former
Vague data
The data or information provided in the argument is too vague to make thorough and justified evaluation about the actual situation
The information concerning is not accurate enough to evaluate the actual condition
The author only inform us that the percentage or fraction of the sub-group in the general group but we do not know the base mount of
Lack of fraction the author only provide us the many or few however, we need to know the fraction of the general group actually
If the base amount or corresponding fraction varies, the conclusion would be different.
For lack of detailed information about we can hardly assess
Incomplete information
Information provided in the argument is incomplete to make thorough and justified evaluation about the actual situation.
Point out that the information provided by the author is incomplete. We need more accurate information about the cases studied, or some other information that is more pertinent to the argument should be provided to assess the problem
The author does not provide complete information concerning
For lack of detailed information about, we can hardly evaluate
False analogy
The author recommends an institution to copy the actions or policies of another institution, while actually the two institutions are not comparable.
The two institutions are comparable at every critical aspect.
Incomplete comparison, changing scope
In the argument the author recommends A to carry out the same policies as B. but we may ask that whether A and B are similar enough at every aspect and are indeed comparable.
While it is true that A and B share some common grounds on
There are still some obvious differences between them
Before A decides to copy Bs experience, the author should take these differences into account and make careful study on the comparability of the two.
Incomplete comparison selective comparison ex parte information
To point out that the author compares only selective aspects of the two subjects or provides information about only one side, and we need to know if other factors that would influence the result are equal in each case, or more detailed information about the other side.
Pointing out that the comparison between the subjects might be incomplete or selective.
The author hastily implies that A is superior to B in, but the comparison between A and B in incomplete, the author only compare however, there are myriad of factors which, if differ in these cases, would bring about totally different result for the comparison.
To fully evaluate the of A and B, the author should provide more concrete evidence about other factors that would influence the result while ignored by the author in the argument.
Without any further consideration about these factors, the author could not convince us that A is better than B, merely based on incomplete comparison.
Confusing comparison and variation
The author provides only the variation about certain subject on certain aspect, while in fact, the comparison between the subject and its counterparts in needed to evaluated the argument, or vice versa.
Lack of controlled experiment, incomplete information
Pointing out that the author provides only the variation of certain subject, or vice versa.
The author provides the variation in to illustrate that
Although the variation in could partly indicate
We all know that to demonstrate the comparison between A and B is actually more convincing and necessary
The author should provide the comparison between those entities to illustrate the conclusion lacking comparison between we could not assess if
Unrelated concepts
The author uses term A to infer term B while actually there is no direct logical relationship between the two terms
In illustrating the assumption that the author commits a fallacy of hasty generalization
The author mentions A however A is not a good indication of B
There are fundamental differences between A and B thus A could not be used to properly illustrate B
The author ought to make careful and clear differentiation between A and B before we could evaluate if the inference that is justified.
Changing scopes
The argument generalize from the condition of some individual cases to a general principal or conclusion which is intended to be applied to a wider range of subjects, or reversely, applies the condition or characteristics of certain general group to some group to some individual cases in that group
To fully evaluate the argument we may well ask that whether the condition of an individual case could sufficiently illustrate the condition of a larger group of subjects
Although the authors inference that might be true for some cases, for example
Unfortunately, this is not true of every individual in the general group
Other subjects may have totally different situation thus the authors inference could not be properly applied to them
Unless the author can demonstrate that the condition of other subjects is similar to that of the case studied, the conclusion cannot be reached basing on special and limited cases.
Inferring a future condition from a past condition
The author suggests that we can solve current problems or achieve current goals through methods which successfully solved the same kind of problems in the past.
A hidden assumption behind the argument is that all conditions and factors upon which the effectiveness of the method depends have remained unchanged during the past
However, many factors could have been changed
Many conditions and factors could have varied which might render the solution which were proved to be effective in the past ineffective in present time or in the future
Without taking into account all these changing factors, the author could not convince us that the proposed solution could be effective in solving current problems
Failing to weigh the advantage and disadvantage thoroughly
The author overemphasizes the advantage of certain action, while ignores the opposite effect. Specifically the author hastily advocates adopting certain actions. While in fact, that series of actions might bring about undesirable consequences or the author hastily proposes to abandon certain actions, while those actions might actually bring about benefits.
In claiming that, the author needs to do comprehensive research on both positive and negative effects of the proposal
Although the proposal could solve the problem to a certain degree,
Carrying out the proposal could actually bring about more harmful effects
Under such scenario, adopting the authors proposal would harm rather than benefit
False dilemma
In explaining , the author is presenting a false dilemma.
The author simply assumes that the situation would be either A or B, while the two are not necessarily mutually exclusive
Many other solutions could exist or could be more reasonable.
Before ruling out all the possibilities above, the author could not convince us that there are only two possible explanations for us to accept
Non causal relationship
The author unfairly assumes that it is that resulted in
But we find no concrete evidence to substantiate the inevitable relationship between and
Many other factors could also lead to the result the author should conduct controlled study to demonstrate the causal relationship
In short, the author could not hastily conclude that is the only possible reason for before taking the above factors into account
Confusing the cause and the effect
In the process of reasoning the author implies that A is the reason for B.
However, the author may confuse the cause and the effect.
The author fails to rule out the possibility that
Without adequately taking this possibility into account, the assumption that is untenable.
The confusing concurrence with causality
To point out that there is no substantial evidence that could prove the causal relationship or to point out that there are many other alternative explanation which could also explain the result or to point out that the comparison between counterparts should be conducted to substantiate the causal relationship
The most important problem is the underlying assumption that it is that resulted in
The author only points out that the two events occurred during the same period
However we all know that merely a coincidence of two events could not sufficiently demonstrate a causal relationship between them
Many other factors could also lead to the result the author should conduct controlled study to demonstrate the causal relationship
Without ruling out such factors we could not be convinced that is the actual cause of
Post hoc, ergo propter hoc
The author assumes thatis responsible for
basing on the mere fact that occurred after
however, the sequence of the two events in itself does not sufficiently prove that the former caused the later
Many other factors could also lead to the result
might have resulted from other factors such as
Without ruling out these possible scenarios, the author could not establish a causal relationship between and
Sufficiency and necessity of a solution
The author proposes a solution to attain certain objective while in fact the solution is neither sufficient nor necessary for the purpose.
The author assumes that the proposed actions are both sufficient and necessary for attaining certain objective
Adopting the action alone, however, may not ensure solving the problem
To attain the authors objective, many other fundamental requirements must be fulfilled.
Furthermore, other available methods besides the authors proposal could also be used to achieve the same goal
Before the author makes thorough comparison between the effectiveness of his own proposal and other possible methods, the authors proposal should not be hastily carried out.
Failing to consider the feasibility of the conclusion
The solution could not be smoothly carried out due to some obstacles
The feasibility of the augers proposal can also be cast doubt on.
The proposal relies on an assumption that the proposal could be successfully carried out however the assumption might be unwarranted due to some obstacles.
Unless the author could demonstrate that those obstacles could be effectively overcome, the proposal might be practically unfeasible.
Insufficient evidence
The evidence provided by the author is insufficient to reach the conclusion.
The author treats a lack of proof that as constituting sufficient proof that , for the author only points out that
Although the information provided by the author may have little relation with
This piece of information in itself is far from sufficient to demonstrate the assumption that
We need more important information about the case studied.
Unwarranted assumption credibility of the evidence.
The evidence in the argument lacks credibility, or the author provides no effective evidence to substantiate the assumption
The assumption that is open to doubt.
Since the author does not provide any evidence to substantiate the assumption, many other possibilities might render the assumption suspect.
Given other possibilities about the author could not hastily assume that
Definition critique
Definition of certain critical term in the argument is vague, or the term has no essential logical relation with the conclusion.
One problem involves how author defines
The definition might be different from what we commonly consider the term to be.
As we commonly accept, the term usually means a meaning other that the authors understanding.
Therefore, if the term is defined as other ways, the evidence cited by the author is irrelevant to the authors conclusion.
In one word, without a clear definition of , it is impossible to assess the strength of the argument.
Negative evidence
The author cites the evidence that to convince us that
However, this piece of evidence may well prove an opposite situation and could seve to refute the authors assumption. The author should provide more convincing evidence to reconcilethis apparent self-contradictory claim.
Profit-cost analysis
The author hastily claims that we could earn great profits by adopting certain proposal, but fails to analyze the possible cost of doing so.
Even if the authors proposal could be carried out effectively, we still could not hastily assume that will necessarily earn a substantial profit, as the author predicted.
To evaluate the profitability of we should consider the function of both revenue and expense.
However, the author does not provide any information about the possible cost of carrying out the authors proposal
Many key steps of the proposal may involve great expense, if the cost of carrying out the proposal exceeds projected revenue the proposal would be profitless.
Without more information about production costs, it is impossible to assess whether carrying this proposal will be effective or profitable.
Lack of controlled experiment or comparison
The author ought to conduct controlled experiment or to make comparison between the subject and its counterparts to illustrate the causal relationship between two events but no such evidence is provided.
The author unfairly assumes that it is that resulted in
The causal relationship is convincing only if the author could demonstrate that all other factors that might affect the result remained constant during the same period.
Specifically, we need to know the experiment result of one group of the subjects, while at the same time, we also need to find out the situation of the counterpart.
Without appropriate comparison between one group and its counterpart, the assumption that is unwarranted.
Economic factors
The author fails to take the inflation rate into account, or fails to analyze the relationship between the demand and the supply of certain product when drawing economics-related conclusion
Also, some economic factors should taken into account in the argument.
First, we need to know how much did the price of actually increase after adjustment for inflation.
Second, the author fails to consider the variation in the demand for during the same period
If the supply of falls short of demand, then there is good reason for the increased price of
The soundness of the speakers claim is significantly weakened for lack of economic consideration.
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