Part 2: 1 Introduction I have a number of purposes in mind as I write Part 2. You can read these in conjunction with Figure 4. 2.4 Appreciating epistemological issues Common sense tells me my experience and understanding of the world are limited. I am 173 cm in height. That limits my view of the world. It may not matter much that I cannot see what my house looks like from above but it does mean there will be things going on in the roof I may not notice until they impinge on areas that I can experience. More significantly, there is a real limitation on understanding the experiences of other people. You might tell me about your experience but your desc 2.2 The nature of systems thinking and systems practice There are no simple definitions for either systems thinking or systems practice. It's difficult to find definitions that capture all the perspectives that the ideas carry for people who think of themselves as systems thinkers and systems practitioners. Most systems practitioners seem to experience the same kind of difficulty in explaining what they do or what it means to be systemic in their thinking. Through experience I've developed some criteria by which I characterise systems thinking, bu 12.3 Market pull The alternative market pull model suggests that the stimulus for innovation comes from the needs of society or a particular section of the market (Figure 55). These might be needs perceived by an entrepreneur or manufacturer like Shaw and his cat's-eyes or they m 10.9.2 New technology The appearance of a new technology often results in the possibility of developing a whole range of new products. The invention of the transistor in the USA by Bardeen, Brattain and Shockley in 1947 led to a vast market of improved consumer electronics goods such as portable radios, hi-fi and television. Later on, the related inventions of the integrated circuit in 1959 (by Jack St Clair Kilby at Texas Instruments) and the microprocessor in 1971 (by Marcian E. Hoff at Intel) allowed the develo 10.5 Desire to help others This is a less common motivation but it shows not everyone is driven by money. In 1991 the inventor Trevor Baylis saw a BBC documentary about the spread of HIV/AIDS in Africa. What was needed was a way of broadcasting the safe-sex message to people in areas without electricity and where batteries for a radio could cost a month's wages. Solar power wouldn't necessarily help as most people who could get to a radio listened in the evening after work. While absorbing this information he ima 1 People-centred designing