I've a personal law predicated upon principle when donating things to charity. If I can't or don't want to use or wear it why would anyone else. Clear line differentiates what gets a new owner and junk marked for reincarnation. Recycling is a beautiful thing. What does that got to do with Tesla and Solar City? Integration. Solar Roof Power Wall 2 and an Electric Car. Inventions which directly solve the environmental imbalanced equation by creating fully sustainable energy source. Resolves economic impropriety with new jobs. Enhances through revitalization community neighborhoods. Bringing folks together. I'd call that social congruency. When creators of Tesla Solar Roof uses their own creation. Installing the system in their own homes. Not only does it speak to principle. Builds trust that the product is good enough. Confidence it will be for everyone. A perfect law to live by. Take a look...