Probably didnt buy the car because he knew it wasnt oil in the centre eh Mickey!!!
Its just bluddy hot rock.What you see coming from volcanoes is whats down there,at least some of it anyway.
In terms of the earth being warmed from the inside out he's right(to a degree),but for probably the wrong reasons.The internal radiactive reactions within the earth do contribute substantailly to the heat generated within the earth(not sure just how much if any contribute to actual earth warming apart from that coming directly from vocanic events and geothermals etc).Its why scientists underestimated the age of the earth prior to radioactivity being discovered and being able to be measured effectively.
