In this argument, the arguer claims that…Although this argument appears to be quite justifiable at first blush, it is in fact ill-reasoned for the following reasons.
To begin with, the arguer rests on the assumption that + [ ]. Quite possible as it is, the arguer fails to offer any evidence to confirm this crucial assumption…….Without ruling out these possibilities, the arguer cannot reach the stated conclusion.
In the second place, one underlying assumption of the argument is……. Nonetheless, no guarantee is supplied to demonstrate that it is necessarily the case, which, for this reason, compromises the argument’s credibility……. The argument would be more convincing if the arguer took these alternative explanations into account.
Last but not least, even if evidences prove to be in favor of the foregoing assumptions, the arguer’s reliance on the assumption that …… is also problematic, resulting in an untenable argumentation. …… Only if the arguer manages to give reasons why these situations are unlikely to happen will he bolster the argument to a better extent.
In a nutshell, the arguer’s argument does not stem from rigorous logics, which inevitably leads to a hasty conclusion. Thus, what the arguer needs to do is to seek for more persuasive evidence and consider the issue from a more comprehensive angle.