An argument's test to convince others with opposing viewpoint may seem like the best test of an argument. While, in general, if an argument can convince someone else with an opposing viewpoint, it is a generally good argument but sometimes, the opposing party might not have all the information regarding the scenarios the affect the argument. Scenarios such as, does the argument hold in all the cases or in only some cases, are there are any scenarios where the argument may fall apart should be known to the opposing in order to consider an argument to be good. Otherwise, the person is hoodwinking the opposing party instead of putting forward a valid argument.
Voting and advertisement are good examples of an argument convincing parties with opposing views. Political leaders convince voters to go out and vote for them. They start canvassing months before the voting begins. The main agenda of this is to convince voters to vote for them. Only if they put forward arguments that convince them, the voters will vote for these leaders. If the political leaders' arguments cannot convincing those with opposing ideas (in this case those who voted for the party opposing this leader) with their arguments, then governments will never change. Thus, if these leaders win the elections, it can be said that they put forward good arguments and convinced people of opposing viewpoints. Considering the other example of advertisements, it can be seen that if companies can get users to switch from the existing products and use the company's product, one can say that they did a pretty good job at convincing the users.
On the other hand, a lot of times, opposing parties don't know about all the variables on which an argument depends. While canvassing for votes, the political leaders never reveal their hidden agendas. A lot of times, their promises that they make never come true. In case of advertisements, if the product that the company sells doesn't do what it is supposed to do or it has some harmful side effects, then it is not the argument that convinced the people to switch their choice of products. People were convinced because they didn't know about all this.
While this essay propounds that an argument's strength depends on the ability to convince others only in the case when all the variables are known to the opposing party, some might argue that it is the job of the opposing party to get all the information out in the open by asking questions. But, it is not pragmatic. A number of scenarios may be there in which the argument fails. It is infeasible to figure out all the scenario
Does an argument's strength depend on its ability to convince others? In some sense, yes. A weak argument can never convince an opposing party. But, all the scenarios in which the argument doesn't hold true should be known to those with opposing viewpoint.