Here’s the context: I was at a site like Buzzfeed (but not Buzzfeed) and there’s a conversation going on, summary of which:Person A: Brexit is a disaster. Will cost thousands of lives.
B: What evidence for that claim?
A: I didn’t think you went in for sealioning, but anyway: there’s items 6 and 20 for a starter.
I knew they were talking about the infamous Yellowhammer document, put out as a worst-case scenario of a no-deal Brexit. I did an analysis of it back in September. (it’s a big fat scaredy-nairdy).
So I went to Yellowhammer before looking up this Sea Lion business.
Item 6: says that if no-deal Brexit is “unmitigated” there may be a disruption to medical supplies. “Unmitigated" and “may”.
(a) It’s not unmitigated. Even in no-deal people are working on mitigations. Not to mention, there’s now a deal.
(b) You really believe the no-one could do anything, about possible road transport delays? Like flying? It is simply unbelievable. For Person A to claim that this would lead to “thousands of deaths" from medicine shortage is delusional nonsensical scaremongering.
Item 20: says that there may be change to social care. And? So what? I won’t bother going into this, because if people are frighted by nonsense like this, they ought curl up in a little ball and never leave home.
So, to “sealioning”:
Sealioning (also spelled sea-lioning and sea lioning) is a type of trolling or harassment which consists of pursuing people with persistent requests for evidence or repeated questions, while maintaining a pretense of civility and sincerity. It may take the form of "incessant, bad-faithinvitations to engage in debate".... The term originated with a 2014 strip of the webcomic Wondermark by David Malki, ...I can see how incessant questioning can become trolling. Conversely calling someone a “sealioner” can be used to shut down debate. As in, you feel something, but don’t have the facts to back it up, and don’t want to be challenged on it, so accuse your opponent of “sea-lioning”.
In the case above, I think Person B was totally entitled to ask where the “thousands” of deaths were going to happen because of Brexit. Person A’s answer doesn’t stand up to scrutiny, for anyone who bothers going to the document. If Person B were to say this, I would not call it “sea-lioning”. I’d call it debate.