When the best answer is that we don’t know

To Aubrey de Grey who dared to put a number on our uncertainty concerning the prospect of comprehensive biological rejuvenation

In the early 90s as a high school student interested in the natural sciences, I went to listen to a talk by Ede Teller, the controversial ‘father of the hydrogen bomb’. Much to my surprise, Teller, in his early 80s  & sitting on the top of a table at the ELTE University in Budapest, answered one question the following way: ‘Erre tudom a pontos választ. Nem tudom.’ which translates as: ‘I know the exact answer to this question. I don’t know.’ This honest bon mot captures an epistemological puzzle: sometimes acknowledging well informed uncertainty is the adequate form of a valid answer. How come?

One problem with seasoned experts in science and technology is that exactly what makes them experts in the first place is what limits them acknowledging when sometimes the exact answer just cannot be provided. But when the scientific and technological question has a potentially long running impact on human society and Planet Earth, acknowledging the lack of a definite scientific position becomes even more challenging. In these cases, not just individual professional credit is at stake but pre-scientific moral integrity and post-scientific political responsibility. 

An emerging prime example for such a problem is scientists, technologists commenting on the possible limits of what we can achieve in terms of human longevity with ever more advanced biomedical technology. How far can we extend healthy life expectancy? Can we possibly break the maximum human lifespan barrier? If yes, when are we going to hit the next roadblock, if ever? Please note that these questions are usually take the form of what philosophers call modal questions, asking about the practical possibility, the feasibility of some science intensive technological scenario. Continue reading “When the best answer is that we don’t know”