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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.

Aircraft inspection

A few months I took this series of photographs while waiting to board a trans-Atlantic flight home.  First, a small ladder was placed in front of the engine.  Then a technician arrived, climbed onto the ladder and spread a blanket on the cowling before kneeling on it and spinning the fan blades slowly.  He must have spotted something that concerned him because he climbed in, lay on the blanket and made a closer inspection.  Then he climbed down, rolled up the blanket and left.  A few minutes later he returned with a colleague, laid out the blanket and they both had a careful look inside the engine, after which they climbed down, rolled up the blanket put it back in a special bag and left.  Five or ten minutes later, they were back with a third colleague.  The blanket was laid out again, the engine inspected by two of them at once and a three-way discussion ensued.  The result was that our flight was postponed while the airline produced a new plane for us.

Throughout this process it appeared that the most sophisticated inspection equipment used was the human eye and a mobile phone.  I suspect that the earlier inspections were reported by phone to the supervisor who came to look for himself before making the decision.  One of the goals of our current research is to develop easy-to-use instrumentation that could be used to provide more information about the structural integrity of components in this type of situation.  In the INSTRUCTIVE project we are investigating the use of low-cost infra-red cameras to identify incipient damage in aerospace structures.  Our vision is that the sort of inspection described above could be performed using an infra-red camera that would provide detailed data about the condition of the structure.  This data would update a digital twin that, in turn, would provide a prognosis for the structure.  The motivation is to improve safety and reduce operating costs by accurate identification of critical damage.

 

Spontaneously MOTIVATEd

Some posts arise spontaneously, stimulated by something that I have read or done, while others are part of commitment to communicate on a topic related to my research or teaching, such as the CALE series.  The motivation for a post seems unrelated to its popularity.  This post is part of that commitment to communicate.

After 12 months, our EU-supported research project, MOTIVATE [see ‘Getting Smarter‘ on June 21st, 2017] is one-third complete in terms of time; and, as in all research it appears to have made a slow start with much effort expended on conceptualizing, planning, reviewing prior research and discussions.  However, we are on-schedule and have delivered on one of our four research tasks with the result that we have a new validation metric and a new flowchart for the validation process.  The validation metric was revealed at the Photomechanics 2018 conference in Toulouse earlier this year [see ‘Massive Engineering‘ on April 4th, 2018].  The new flowchart [see the graphic] is the result of a brainstorming [see ‘Brave New World‘ on January 10th, 2018] and much subsequent discussion; and will be presented at a conference in Brussels next month [ICEM 2018] at which we will invite feedback [proceedings paper].  The big change from the classical flowchart [see for example ASME V&V guide] is the inclusion of historical data with the possibility of not requiring experiments to provide data for validation purposes. This is probably a paradigm shift for the engineering community, or at least the V&V [Validation & Verification] community.  So, we are expecting some robust feedback – feel free to comment on this blog!

References:

Hack E, Burguete RL, Dvurecenska K, Lampeas G, Patterson EA, Siebert T & Szigeti E, Steps toward industrial validation experiments, In Proceedings Int. Conf. Experimental Mechanics, Brussels, July 2018 [pdf here].

Dvurcenska K, Patelli E & Patterson EA, What’s the probability that a simulation agrees with your experiment? In Proceedings Photomechanics 2018, Toulouse, March 2018.