Principle 2. Local Rationality

Principle 2. Local Rationality


People do things that make sense to them given their goals, understanding of the situation and focus of attention at that time

Work needs to be understood from the local perspectives of those doing the work

“Trying to understand why and how things happen as they do requires an inside perspective." Image: NATS Press Office CC BY-NC-ND 2.0

It is obvious when we consider our own performance that we try to do what makes sense to us at the time. We believe that we do reasonable things given our goals, knowledge, understanding of the situation and focus of attention at a particular moment. In most cases, if something did not make sense to us at the time, we would not have done it. This is known as the ‘local rationality principle’. Our rationality is local by default – to our mindset, knowledge, demands, goals, and context. It is also ‘bounded’ by capability and context, limited in terms of the number of goals, the amount of information we can handle, etc. While we tend to accept this for ourselves, we often use different criteria for everybody else! We assume that they should have or could have acted differently – based on what we know now. This counterfactual reasoning is tempting and perhaps our default way of thinking after something goes wrong. But it does not help to understand performance, especially in demanding, complex and uncertain environments.

In the aftermath of unwanted events, human performance is often put under the spotlight. What might have been a few seconds is analysed over days using sophisticated tools. With access to time and information that were not available during the developing event, a completely different outside-in perspective emerges. Since something seems so obvious or wrong in hindsight, we think that this must have been the case at the time. But our knowledge and understanding of a situation is very different with hindsight. It is the knowledge and understanding of the people in situ that is relevant to understanding work.

In trying to meet demand, it is the subjective goals of the people that are part of the system that shape human performance. These goals are situated in a particular context and are dynamic. They may well be different to the formal, declared system goals, which reflect the system-as-imagined (as reflected in policies, strategies, design, etc). Yet it is the formal goals that we tend to judge performance against. While bearing these formal goals in mind (and questioning their appropriateness), analysis should seek to understand goals from the person’s perspective at that time.

The person’s focus of attention also requires our understanding. We might be baffled when a conflict is not detected by a controller, or an alarm is not spotted by an engineer. We might ask questions such as “How could he have missed that?” or say “She should have seen that!” What seems obvious to us – with the ability to freeze time – may not be obvious at the time, when multiple demands pull attention in different directions. Understanding these demands, the focus of attention, the resources and constraints is vital.

Trying to understand why and how things happen as they do requires an inside perspective, using empathy and careful reconstruction with field experts to make sense of their work in the context of the system.

Once one accepts this, it becomes clear that everyone will have their own local rationality; there will be multiple perspectives on any particular situation or event. This does not imply weak analysis, but acceptance that the same situation will be viewed differently. Performance cannot be necessarily understood (or judged) from any one of these. Making sense of system performance relies on the ability to shift between different perspectives and to see the interacting trajectories of individuals’ experiences and how these interact.

Exploring multiple and differential views on past events and current system issues brings different aspects of the system to light, including the demands, pressure, resources and constraints that affect performance. We begin to see trade-offs, adjustments and adaptations through the eyes of those doing the work. This will help to reveal the aspects of the system that should be the focus of further investigation and learning.

Practical advice

  • Listen to people’s stories. Consider how field experts can best tell their stories from the point of view of how they experienced events at the time. Try to understand the person’s situation and world from their point of view, both in terms of the context and their moment-to-moment experience.
  • Understand goals, plans and expectations in context. Discuss individual goals, plans and expectations, in the context of the flow of work and the system as a whole.
  • Understand knowledge, activities and focus of attention. Focus on ‘knowledge at the time’, not your knowledge now. Understand the various activities and focus of attention, at a particular moment and in the general time-frame. Consider how things made sense to those involved, and the system implications.
  • Seek multiple perspectives. Don’t settle for the first explanation; seek alternative perspectives. Discuss different perceptions of events, situations, problems and opportunities, from different field experts and perspectives. Consider the implications of these differential views for the system.

View from the field

Paula Santos, Safety, Surveillance and Quality Expert, NAV-P, Portugal

Facing an unexpected situation, what do you do? Do you try to understand what is going on and what has happened? What can be done to sort it out? Assess the possible consequences of acting versus delaying action? Do you go to look for instructions or manuals when there is time pressure? Do you ask for help? Do you apply what has worked before in similar circumstances? For technicians, apply the stop and start again solution? Depending on the individual, the environment, the time available, the time of day, and many other factors, the understanding of the situation will differ, and so will the response. But, whatever course of action you choose, you will consider it to be the right thing to do at that time. If this is valid for you, it is probably true for many. So why do we tend to forget this principle when analysing what others have done?

Source: Systems Thinking for Safety: Ten Principles. A White Paper. Moving towards Safety-II, EUROCONTROL, 2014.

The following Systems Thinking Learning Cards: Moving towards Safety-II can be used in workshops, to discuss the principles and interactions between them for specific systems, situations or cases.

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