b.p. or exxon mobil or fill in the blank is never actually going to be able to poll a certain percentage ten twenty thirty fifty percent of what they have on their balance sheet on their books they will never be able to pull it out of the ground or stop purse is going to collapse so i mean you know this kind of thing economists have their hair on fire about but it would be a good thing it seems for our planet and that money presumably would just end up going someplace else to other. technology and it was what's. i'm sure you guys have thought about this a lot sure and there's a couple of things that are relevant i think one is that. has said we're going to stay below two degrees which is the to keep global average temperature rise under that limit and that that is sort of the safest most adaptable amount of global warming we can achieve. one hundred ninety countries including the united states have agreed to made a commitment to try to do that and i tells us that if we are going to do that most of those carbon reserves need to stay in the ground so for one that should be the signal right now