Tag Archives: trust

Knowledge is power

Pitt Rivers Museum, Oxford

“The list of things that I believe is, if not infinite, virtually endless. And I am finite.  Though I can readily imagine what I would have to do to obtain evidence that would support anyone of my beliefs, I cannot imagine being able to do this for all of my beliefs.  I believe too much, there is too much relevant evidence (much of it available only after extensive, specialized training); intellect is too small and life is too short.”

These words are a direct quote from the opening paragraph of an article by John Hardwig published in the Journal of Philosophy in 1985. He goes on to argue that we can have good reasons for believing something if we have good reasons for believing that others have good reasons to believe it.  So, it is reasonable for a layperson to believe something that an expert also believes and that it is even rational to refuse to think for ourselves in these circumstances.  Because life is too short and there are too many other things to think about.

This implies a high level of trust in the expert as well as a concept of knowledge that is known by the community.  Someone somewhere has the evidence to support the knowledge.  For instance, as a professor, I am trusted by my students to provide them with knowledge for which I have the supporting evidence or I believe someone else has the evidence.  This trust is reinforced to a very small extent by replicating the evidence in practical classes.

More than 30 years ago, John Hardwig concluded his article by worrying about the extent to which wisdom is based on trust and the threat to “individual autonomy and responsibility, equality and democracy” posed by our dependence on others for knowledge.  Today, the internet has given us access to, if not infinite, virtually endless information.  Unfortunately, much of the information available is inaccurate, incomplete and biased, sometimes due to self-interest.  Our problem is sifting the facts from the fabrications; and identifying who are experts and can be trusted as sources of knowledge.  This appears to be leading to a crisis of trust in both experts and what constitutes the body of knowledge known by the community, which is threatening our democracies and undermining equality.

Source:

Hardwig J, Epistemic dependence, J. Philosophy, 82(7):335-349, 1985.

Can you trust your digital twin?

Author's digital twin?

Author’s digital twin?

There is about a 3% probability that you have a twin. About 32 in 1000 people are one of a pair of twins.  At the moment an even smaller number of us have a digital twin but this is the direction in which computational biomedicine is moving along with other fields.  For instance, soon all aircraft will have digital twins and most new nuclear power plants.  Digital twins are computational representations of individual members of a population, or fleet, in the case of aircraft and power plants.  For an engineering system, its computer-aided design (CAD) is the beginning of its twin, to which information is added from the quality assurance inspections before it leaves the factory and from non-destructive inspections during routine maintenance, as well as data acquired during service operations from health monitoring.  The result is an integrated model and database, which describes the condition and history of the system from conception to the present, that can be used to predict its response to anticipated changes in its environment, its remaining useful life or the impact of proposed modifications to its form and function. It is more challenging to create digital twins of ourselves because we don’t have original design drawings or direct access to the onboard health monitoring system but this is being worked on. However, digital twins are only useful if people believe in the behaviour or performance that they predict and are prepared to make decisions based on the predictions, in other words if the digital twins possess credibility.  Credibility appears to be like beauty because it is in eye of the beholder.  Most modellers believe that their models are both beautiful and credible, after all they are their ‘babies’, but unfortunately modellers are not usually the decision-makers who often have a different frame of reference and set of values.  In my group, one current line of research is to provide metrics and language that will assist in conveying confidence in the reliability of a digital twin to non-expert decision-makers and another is to create methodologies for evaluating the evidence prior to making a decision.  The approach is different depending on the extent to which the underlying models are principled, i.e. based on the laws of science, and can be tested using observations from the real world.  In practice, even with principled, testable models, a digital twin will never be an identical twin and hence there will always be some uncertainty so that decisions remain a matter of judgement based on a sound understanding of the best available evidence – so you are always likely to need advice from a friendly engineer   🙂

Sources:

De Lange, C., 2014, Meet your unborn child – before it’s conceived, New Scientist, 12 April 2014, p.8.

Glaessgen, E.H., & Stargel, D.S., 2012, The digital twin paradigm for future NASA and US Air Force vehicles, Proc 53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, AIAA paper 2012-2018, NF1676L-13293.

Patterson E.A., Feligiotti, M. & Hack, E., 2013, On the integration of validation, quality assurance and non-destructive evaluation, J. Strain Analysis, 48(1):48-59.

Patterson, E.A., Taylor, R.J. & Bankhead, M., 2016, A framework for an integrated nuclear digital environment, Progress in Nuclear Energy, 87:97-103.

Patterson EA & Whelan MP, 2016, A framework to establish credibility of computational models in biology, Progress in Biophysics & Molecular Biology, doi: 10.1016/j.pbiomolbio.2016.08.007.

Tuegel, E.J., 2012, The airframe digital twin: some challenges to realization, Proc 53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference.