A: When you change the level of detail to look at trends and combine it with theory and experiments and known knowledge then you can make reasonable forecasts. Improving trends are not destiny and require a lot of effort to sustain. The famous Moore's law is an example. Everytime people looked a few cycles out (5-10 years) they would see big technical, process and business hurdles. Some thought that they would be impossible to overcome. A lot of hard work (tens of thousands of scientists and engineers and managers) and clever research and strategies kept the progress going.
Q: The predictions of technical capability and social impact seem beyond my world view of what is reasonable. How can it be ?
A: Most people do not track technological, business process or scientific progress in detail. It takes a lot of time, because there is a lot happening. Therefore, most people have a flawed world view in terms of predicting the technological future. Many people underestimate how cleverly visionary engineers, scientists and entrepreneurs can combine things now or reasonably could in the future to overcome difficulties in development and implementation. Most people do not appreciate the 2-7 or more years it takes to take something from the lab out as a product and what actually happens to make that happen. Some people assume that when someone projects a successful commercialization of a lab development that the predictor is ignoring the hard work, funding and cleverness that will be needed to make that happen.
Molecular nanotechnology is particularly difficut for people to accept because it involves multiple interactions. More to follow.