Why is there something rather than nothing?

I found an interesting philosophical argument map supporting the claim that science cannot explain everything at:

http://www.optimizelife.com/wiki/Argument_maps

I have presented it slightly differently using Rationale, since I believe the (circled) claim that "It(e) therefore cannot be answered by an appeal to any part of the spatiotemporal universe" is superfluous:

You can download the rationale file here: Download why_is_there_something_rather_than_nothing.rtnl