The Ordinary Conception of Logical Consequence
Another note on FOL75: In his talk, Wilfried Hodges argued that the logician's conception of logical consequence differs a lot from the ordinary conception. One of his points was that not all valid arguments are valid in any of our technical senses because the latter don't account for conceptual implication. That's of course true. But Hodges also claimed that consultation of Google shows that the ordinary conception of logical consequence is even further away from what most logicians think. For if one excludes results from sites about philosophy and logic the top results (e.g. 1, 2, 3, 4, 5) all look like this (from 5):
Consequences can be natural or logical. A natural consequence automatically follows the behavior: a child runs out into the snow without shoes and he gets cold. A logical consequence is delivered by the parent: a child runs out into the snow without shoes and his mom carries him back into the house. [...]
A logical consequence is a real choice. Both options must be acceptable to the parent. For example, "Pick up your toys now or I will put them away for two days."
I don't find this convincing, and not only because this other technical use of "logical consequence" doesn't exist in German. We should distinguish between the ordinary conception of logical consequence and the ordinary conception (or usage) of "logical consequence". I don't care much about the latter.