The plant manager’s argument is vulnerable to this criticism. Just because adopting the new process would have some costly aspects, that doesn’t necessarily mean that the new process would bring the company no profit.

The plant manager never cites his authority as support for his conclusion. He cites the costs associated with adopting the new process.

This is the cookie-cutter flaw of circular reasoning. The plant manager doesn’t make this mistake. Instead, the plant manager overlooks the possibility that the financial benefits of the new process could outweigh the cost and bring the company a profit.

The author doesn’t cite any probably true evidence. He only cites definitely true facts, but those facts aren’t sufficient to prove his conclusion.

The fact about the sulfur dioxide output of the plant is the only fact the plant manager mentions that isn’t directly relevant to the overall conclusion of the argument, but that fact isn’t treated as if it supports the overall conclusion.