Newspaper editor: Law enforcement experts, as well as most citizens, have finally come to recognize that legal prohibitions against gambling all share a common flaw: no matter how diligent the effort, the laws are impossible to enforce.
Conclusion
There should be no law against gambling.
Evidence
If a law fails to be effective, then there should be no law.
Gambling laws are impossible to enforce.
Evaluate
We might hear the missing link here, but it's been well disguised with filler phrases and qualifiers like "Ethical qualms notwithstanding" (jerks).
When we're doing Sufficient Assumption, it sometimes benefits us to think of the conclusion as a logic voneyor belt we need to build.
Proving that "there should be no law against gambling" could look like,
Gambling ---------------------------> should be no law
The arrow is intentionally elongated because we're trying to create a space in which we can see what ideas were presented, and how the author's train of thought was designed to work. We want to ask ourselves questions about the conclusion:
- What were we told (if anything) about gambling?
- what rule were we given (if any) that allows us to derive the idea that there "should not be a legal prohibition".
The second to last claim gives us a mechanism for proving that there shouldn't be a law.
If we can establish that a law fails to be effective, then this rule lets us derive that there shouldn't be a law. So if we knew that gambling laws aren't effective, then that would prove our conclusion.
Did they tell us that gambling laws are ineffective? No, they told us that gambling laws are unenforceable.
So we need to get from "unenforceable" to "ineffective". Visually, it looks like this:
CONCLUSION Gambling -----------------------------> should be no law EVIDENCE Gambling --> imposs fails to should be to enforce to be --> no law effective
MISSING ASSUMPTION
imposs fails to to enforce → to be effective
If we could make that internal connection, then we would have our desired logical conveyor belt from Gambling to Should Not Be Law.
Goal
We want an answer that says impossible to enforce → ineffective law
But we know on Sufficient Assumption they often present what we're looking for in contrapositive form, so we can mentally prepare as well for effective law → possible to enforce