Why non-contradiction matters
The first step in any debate about COVID should be to avoid logical inconsistencies
Aristotle once suggested that rational discussion is impossible without the concept of non-contradiction. After all, how can we make discoveries or reasoned arguments if we are happy to claim that something is true while also claiming that it is not true?
COVID is one of those topics that will be dissected for decades and beyond, in part because data were so patchy early in the pandemic (and, in many cases, sparse late in the pandemic too). But before debating the details, we must pass Artistotle’s more fundamental test: we need to make sure we aren’t contradicting ourselves.
Below are three (non-exclusive) examples of situations where I’ve noticed contradictions occur. If we want to understand better what happened with COVID – and develop better approaches for the next pandemic – the first step will be to avoid such inconsistencies.
Impact of vaccines
Vaccines were one of the major COVID success stories. In 2020, susceptible populations were battered by epidemic waves, from Manaus to New York. But in 2021, as-yet-uninfected individuals could now build immunity through vaccination.
In August 2021, a Public Health England report estimated that COVID vaccines had so far prevented over 100,000 deaths in England. Politicians and journalists lauded the achievement, often quoting this figure.
However, if in early 2020 you’d shown these same people a hypothetical modelled scenario – perhaps with fewer control measures – that led to over 230,000 deaths by mid-2021, I suspect some would have said it was impossible. For context, Imperial College’s widely discussed Report 9 estimated there would be around 250,000 COVID deaths in Great Britain with only moderate ‘mitigation’ measures (i.e. case isolation, household quarantine and social distancing of the elderly).
Regardless of your views on a specific modelling analysis, if you argue that vaccines prevented 100,000 deaths up to the end of August 2021, then by definition you are also arguing that there would have been an additional 100,000 deaths in a scenario without vaccines. Given there were over 130,000 reported COVID deaths by August 2021, this would imply over 230,000 deaths in a ‘no vaccine’ scenario. As much as people might like to try, it’s not possible to argue one of these things without the other.
First lockdown vs second
In October 2021, the House of Commons and Science and Technology Committee and Health and Social Care Committee published a report titled Coronavirus: lessons learned to date. It’s important to document and debate what happened during the pandemic – and identify relevant lessons – but some journalists rightly questioned the conclusions of the following paragraph in the report:
Let’s breakdown the claims involved. The first point about counterfactuals seems a bit muddled, as this would apply to both lockdowns. Why was the impact of an earlier first lockdown knowable, but the impact of an earlier second one not?
What’s more, the emergence of Alpha didn’t change the fact that hospitalisations and deaths were already at high levels in autumn 2020. When the March 2020 stay-at-home order came in, there were around a thousand people in ICU with COVID; when the November 2020 stay-at-home order came in, there were also around a thousand people in ICU with COVID. So it’s inconsistent to claim that earlier measures would have reduced the impact when cases were known to be rising in first wave, but wouldn’t have reduced the impact when cases were known to be rising in second wave.
What happened in Sweden
Sweden had one of the most intensively discussed responses to COVID. As well as decision-making during the pandemic, it’s also likely that pre-pandemic factors influenced the epidemic there. In particular, the country has a lot of single person households and a relatively generous sick leave package. COVID transmission risk is generally much higher among household contacts, so perhaps it isn’t that surprising that it was easier to get transmission down than in other countries, because people could i) affort to isolate; and ii) were less likely to infect others while isolating.
But rather than discussing the nuances of population structure and societal support, and trying to untangle how these combined with other factors to influence transmission, the debate around Sweden has often got stuck at contradictory soundbites.
Some commentators and media outlets have got themselves into a particular muddle when it comes to Sweden. I’ve seen the two following claims made repeatedly:
Despite a paucity of stringent top-down measures, there was massive behavioural change in Sweden, on par with the reduction in interactions in other European countries. This drop in social contacts brought transmission down without the need for extensive government mandated restrictions.
Life in Sweden during the pandemic was mostly normal, with little change in behaviour. Social distancing had no effect on the epidemic and transmission came down for other reasons (e.g. seasonality, hidden immunity etc.)
These two claims can’t both be true. And it’s impossible to have a constructive discussion if people happily switch between them, depending on which happens to suit them on a given day.
When it comes to discussing COVID, we needed – and still need – a much better standard of debate. It’s one thing to use evidence to counter arguments made by someone else. It’s another to stumble at the starting gate by contradicting yourself.
If you’re interested in reading more about the key questions we need to address ahead of the next pandemic, this post has more:
We aren't prepared for the next pandemic
It will probably start with a cluster of unusual symptoms. Some of the people with the disease will know each other, but won’t have been exposed to animals, suggesting the infection can spread between people. Then more cases will start appearing in other areas, maybe even in other countries.