What can I say about David Blockley? Many things. That he has been very influential on engineering thinking, even though not as immediately influential as perhaps he had hoped because of inertia and because he is consistently ahead of his time. Which, of course, is what you would want in a leader. And he has been ahead of his time because of an insatiable curiosity as to ideas and possibilities and an almost moral crusade to do things properly – which means doing things differently. He asks probing questions: What are the real causes of failure? How can we assess its likelihood in a way that we can use our engineering skills to reduce the hazard or balance it to an acceptable level? What do we mean by likelihood anyway, and are there better measures than probability? What are the real problems facing engineers as opposed to those we are accustomed to assume? And how can we think better, act better and be more focussed and effective as engineers?
These questions lead inevitably to a systems approach. The real problems, the difficult problems of engineering are generally messy and need a holistic approach. They need skills absent from the normal and restricted curriculum of engineering schools. And so David has often brought in allies from other disciplines – Pidgeon from psychology, Turner from sociology, Baldwin from mathematics for instance – to deepen the discussion and introduce techniques and insights not normally familiar to engineers.
The systems approach is not easily systematised, so to speak, partly because of the breadth of the issues involved, but more generally because there is no narrow set of applications allowing development of an easily focussed theory. Structural analysis, for example, has techniques fine-tuned to dealing with structures, but the systems approach can be applied to anything. It has no natural boundaries. What is needed is not so much a set of immediate techniques as general principles and overarching concepts for giving the approach its power and its constraints. Thus, for example, David identified the importance of a process view of systems, and of thinking in terms of holons. The trap is to avoid being so general as to be ineffective; hence specific guides and ideas are needed. These are found aplenty in David's work, with the best and most practical instances being summarised in Doing it Differently, written with Patrick Godfrey. It should be on every engineer's bookshelf.
Safety has been an ongoing theme, starting from David's influential 1975 ICE paper ‘Predicting the likelihood of structural accidents’ and the related book The Nature of Structural Design and Safety, with his systems approaches growing from these. But his mind has ranged more broadly, so that, for example, he produced the New Dictionary of Civil Engineering in 2005, and the more recent Bridges, which is aimed at the lay public. As well as discussing bridges and their nature in an approachable way, the book tries to convey basic systems ideas. It is no easy matter.
So I see David as a leader and a crusader with an intense moral drive to change the world, to show how to do things better and see more clearly. His efforts have been well and rightly recognised – by his presidency of the Institution of Structural Engineers for example. His influence is already significant. It will continue to grow.