This is a very difficult situation. I have seen situations where the creative has an aversion to the "business" side. In truth even the creative portion is a single pillar of the entire business structure. I have yet to see a business succeed without a business plan even if the creative team is excellent. There needs to be some form of road map so everybody is on the same page with respect to the company goals. Without this "map" the business is without direction. I would be happy to have a conversation and go through scenarios to help you have a heart-to-heart with your partner. We could also go through some case studies as proof for why the business plan is for his benefit. If you are not on the same page on this foundation elements you will have little chance of success.