Can medical tests ever be absolutely certain?

In a recent high court case in Ireland, a Judge in the High Court ruled in a precedent-setting decision that in delivering an ‘all-clear’ result from a cervical smear test, the lab should only do so in cases where they have absolute certainty. The language used has raised significant concerns, as such a threshold is seen as too high to reach. As cancer specialist Prof Donal Brennan told RTE, there’s very little that is absolute in medicine; one presumes he was thinking of death as the sole exception to the rule. The reaction briefly opened up a dialogue on science and knowledge, truth and epistemology, revealing a fundamental flaw in the human condition, and just as quickly it closed again.

moon surface
The lunar surface, photographed in 1966.

Since the second world war, our politics has become increasingly distant from people. Voter participation has declined, distrust in politicians has grown, and corruption perceptions have increased in many jurisdictions. Inequality has accelerated as those with the highest wealth and income acquire ever greater resources – far more than they can reasonably consume – while those at the other end of the economic spectrum see their lot diminish. The relationships between commerce and politics have deepened as free market policies have governed national policy in western liberal democracies across the range of services, from social welfare and healthcare to infrastructure and defence. These institutions, invested with authority and legitimacy by democratic processes, appear foreign to the people they claim to serve; their values – of costs, efficiencies, and performance – seem distant from their clients. These institutions often instil fear, driven as they are by objectives of enforcement, compliance, and law.

Lotfi Zadeh, inventor of fuzzy logic, who died earlier this month at the age of 96.

I’ve long had an idea about the curved nature of things, the non-binary natural order. This is not the same as relativism versus absolutism, which is one sense a binary opposition in itself; rather, it is a straight acknowledgement that truth is never fully observable, that is it at least always subjective, and that even in the subjective moment it is mutable. What I see may not be what you see; and what I see is inconstant. Time impacts on that observation such that its character is unstable. Take pain and pleasure, for example. While on the one hand some people take a kind of satisfaction from pain, and are attracted to it, whether physical or emotional, so too others recoil from pleasure, perhaps based on guilt, or other psychological alignments. Still further, the same act – a touch – can bring immediate pleasure, while the same act, more forcefully applied, can either increase the pleasure or turn at some point to pain.