Investing

Investing in specific, technical domains is a bet I have hard time deciding upon. I had conversations the past day with people who in their own domains have a kin perception on where the needs may be for interpretation work. It's highly specialized stuff like neutraceutical. Embedded systems told another one. I went back home and put an order on the first subject for books in English, French and Japanese. However, the decision to work hard on any very focused subject with the dim prospect that there might be a continuously growing stream of demand is tricky and always has been so. What about photovoltaic devices, fuel cells? I indulged in many other books on these as well and will consult with other people "who know". It's not that investing in specific domains is a loss of time but a few past experiences have shown the limit of betting into the future of this over that. In the meantime, I looked for hints, not a miracle cure, at how other people proceed when trying and learn fast about a new subject. Nothing revolutionary of course and a split between the "read as much as possible even if you don't get it right away but don't go back", to the "read and reread until you get a clearer picture." The two tribes seem not to agree with each others.