1: Some households that now skip recycling are held back only by the lack of pickup on their street. · 2: A refundable deposit would lead residents to return containers rather than discard them and forfeit the deposit.
The two officials recommend different fixes, and each fix rests on an unstated assumption. The columns ask you to find the assumption that holds up each side. The test for an assumption a recommendation depends on is to deny it and see whether that side's case falls apart.
The Sato side. Sato wants to expand pickup so that households on streets without it can recycle. For that to raise the recycling rate, there have to be households that are currently kept from recycling only by the missing pickup, households the new service would actually convert. Deny it, suppose no current non-recycler is held back solely by the lack of pickup, and expanding pickup converts no one, so Sato's recommendation does nothing. Because its denial sinks the case, the recommendation depends on it. That is the assumption Sato's recommendation depends on.
The Trahan side. Trahan wants a refundable deposit because residents have no reason to return containers now. For the deposit to raise recycling, it has to make residents bring containers back, not simply pay the deposit and throw the container away anyway. Deny it, suppose residents just absorb the small deposit and keep discarding containers in the regular trash, and recycling does not rise, so Trahan's recommendation fails. The recommendation depends on the deposit actually pulling containers back. That is the assumption Trahan's recommendation depends on.
That many households do not recycle because no pickup is offered is a premise Sato states outright, not the hidden assumption his case needs; a stated premise is given, not the thing the recommendation secretly rests on. The cost comparison weighs the two fixes against each other, but neither recommendation's logic depends on its own fix being the cheaper one. The two absolute statements, that no household with pickup has ever failed to recycle and that every non-recycler lives on a street without pickup, are far stronger than either recommendation requires; Sato needs some non-recyclers to be access-blocked, not a guarantee that every non-recycler lacks pickup, and his case does not need a perfect record on streets that already have it.
The discipline: an assumption a recommendation depends on is the unstated claim whose denial sinks it, not a premise already stated and not a stronger-than-needed absolute.
Sato depends on: some non-recyclers are held back only by the missing pickup. Trahan depends on: the deposit brings containers back rather than being forfeited.