'I hate energy topics. Ah I say, I say that with great vehemence. You're dealing with something which is an abstraction. You can't put concrete, concrete items in front of them and say "that's it" ... I'm, I'm telling you that it's with some trepidation tht I start each year and I sigh deeply. And really I'm teaching it because I have to - it's in the syllabus." (T22, Px, 30).