The subtlety of bottom up design

A great problem I had in writing this chapter was in being able to explain the difference between top down and bottom up approaches when it applied to finding and taking advantage of opportunities.

I made several attempts, but, the descriptions of a bottom up approach seemed to come out as just a different way of describing a top down approach. For example, an opportunity opens up to create a solution to a problem. The components in the cafe are examined to see if some mix or combination can provide a solution. Isn't this a classic top down approach, where the requirements of a solution are determined before the components are assembled?

A bottom up approach is about not even knowing what the problem is, let alone knowing the solution. Yet, the idea that you have a solution space full of possible solutions does suggest that you have to start with ideas and opportunities first. Either I was fooling myself about using a bottom up approach, or, some crucial element was missing from my explanation.

This same thought troubled Tillman Pearce, the medical director of an oncology business unit for a large pharmaceutical company in France. Writing to a table of readers in the virtual cafe, he provided an interesting parallel in the medical world:

I have been going over chapters 5 and 6 trying to decide what I think before communicating with the group. I am having difficulties putting things together.

Part of the problem I think we all are having is going back and forth between bottom up and top down thinking. A good figure to use in visualizing this is Figure 7.4. The bottom up is to look at the business assets, skills, and capabilities, and "wait" for the Star Trek type concretization to manifest itself as the right idea. On the other hand, we are all thinking of a good idea to apply our resources to, but, then we are applying a top-down approach.

As I am a physician, I relate this to the process of approaching a patient with an uncertain diagnosis. A good physician switches back and forth between two different modes: he has studied physiology, and the pathology of disease and comes to the bedside with these concepts, or boxes, in which he tries to place the patient's signs and symptoms.

This conceptual approach is obviously necessary as a pattern detection device. On the other hand, it can also blind you to the less than obvious since you risk seeing only what you want to see in order to satisfy the pre-established concepts you brought into the patient's room--- this top down approach works 90% of the time, but obviously depends on how learned is the physician.

A gifted clinician knows how to suspend his judgement and allow his percepts – sight, smell, touch, sound-- to simply observe what is before him. This phenomenological activity of letting things appear as they are is a technique for breaking out of the ruts which your learned concepts place you in – you proceed in this case from the particular (raw sensory inputs, navigation markers) to the general (a diagnosis), i.e., bottom up.

This technique is particularly useful in resolving a difficult diagnosis. However, what usually happens is that all signs and symptoms lead to a seemingly obvious but incorrect diagnosis, yet, a single isolated finding, which doesn't fit the general picture, can lead to discovering a seemingly less likely but more accurate diagnosis. Others discount the anomalies and thus miss the point.

Tillman Pearce

It is just such a similar situation that occurs for cafe owners. Opportunities and ideas are very much like diagnoses: they are possible end solutions. To start with these would necessitate working backwards from them. It would suggest configuring the component's in the cafe to test each possible opportunity or idea to see which of them would provide the best fit for the components in a cafe owner's cafe. This is a top down approach, when what is really needed is a bottom up approach.

The two different approaches to clinical diagnosis as described by Tillman Pearce illustrate perfectly the subtle difference between a top down and a bottom up approach. In the top down approach, an experienced physician knows of a number of possible solutions to the problem of what is wrong with the patient. The symptoms are then used to see which of these solutions provide the best fit to explain what is wrong with the patient.

This can be compared to a cafe owner having many ideas and opportunities and then choosing the idea or opportunity that most closely matches the skills and knowledge available in the cafe. The cafe owner's choices are limited to those that are known.

Tillman Pearce's second physician, on the other hand, doesn't have any preconceived ideas as to what the solution might be. This allows for the possibility that the solution might be outside of all the solutions that he or she is currently aware of. By looking at all the symptoms and concentrating on what symptoms cannot be accounted for, the clinician will be able to look outside of the limited range of the probable to the much wider world of the improbable where a breakthrough solution might be found.

Looking for solutions outside of the probable? Isn't this the way Sherlock Holmes solved his mysteries and didn't the creator of Sherlock Holmes, Arthur Conan Doyle, base this character on an eminent Scottish physician, Dr. Joseph Bell, who was Conan Doyle's professor when he was studying to become a doctor?

Writing in the final decade of the nineteenth century, Dr. Bell, upon whom Sherlock Homes' character was based, commented on Conan Doyle's work and the techniques of detection that had been ascribed to Sherlock Holmes. He wrote:

Dr. Conan Doyle has made a well-deserved success for his detective stories, and made the name of his hero [Sherlock Holmes] beloved by the boys of this country by the marvelous cleverness of his method. He shows how easy it is, if only you can observe, to find out a great deal as to the works and ways of your innocent and unconscious friends, and, by an extension of the same method, to baffle the criminal and lay bare the manner of his crime

Dr. Bell then carried on to explain that the secret of the detections is not simply the observation of detail, but, the ability to relate it to some specialist knowledge. He wrote:

The great broad characteristics which at a glance can be recognised as indicative of heart disease or consumption, chronic drunkenness or long-continued loss of blood, are the common property of the veriest tyro in medicine, while to masters of their art there are myriads of signs eloquent and instructive, but which need the educated eye to detect.

A fair-sized and valuable book has lately been written on the one symptom, the pulse; to any one but a trained physician it seems as much an absurdity as is Sherlock Holmes' immortal treatise on the one hundred and fourteen varieties of tobacco ash. Trained as he has been to notice and appreciate minute detail, Dr. Doyle saw how he could interest his intelligent readers by taking them into his confidence, and showing his mode of working.

He created a shrewd, quick-sighted, inquisitive man, half doctor, half virtuoso, with plenty of spare time, a retentive memory, and perhaps with the best gift of all the power of unloading the mind of all the burden of trying to remember unnecessary details. Holmes tells Watson: "A man should keep his little brain-attic stocked with all the furniture that he is likely to use, as the rest he can put away in the lumber-room of his library, where he can get it if he wants it."

Note: A full version of Dr. Bell's commentary can be found on the Web at: http://calibercomics.com/SHERLOCK/sherlock-holmes-Dr.%20Bell.htm

Mapping this technique across to a cafe owner who has a solution space: the solution space is not first filled with ideas and opportunities (to see which would be the best fit for the skills and knowledge represented by the people in the cafe). The cafe owner would start with the components in the cafe, playing around with various configurations and then search for ideas and opportunities that would be a suitable match. The ideas and opportunities identified in this way would then be placed into the solution space – for further investigation.

In other words, the cafe owner shouldn't be organising and configuring the people and components in the cafe to provide solutions to known problems: the cafe owner would be starting with the components and looking to find a suitable problem that might be solved by means of this unique mix. The system of components is fixed; it is the ideas and opportunities that have to be changed.

Perhaps this situation is best seen in the way Mother Nature employs this strategy. Mother Nature's equivalent of a cafe full of people and concepts is an ecosystem. When new life forms are introduced into this ecosystem, it is the life forms that have to be compatible with the environment. Mother Nature doesn't reconfigure the environment to cater specifically for new life forms.

This interaction of the life form with the environment may result in them both changing as each adapts to the other, but, the starting point is with the ecosystem – and the kind of life forms that it can sustain.