How the author failed to explain this abbreviation is beyond me. Who in their 50s doesn't know that you spell out important concepts and key terms, then shorten them in parentheses?
He also haven't looked into the strong philosophical arguments for BI, dating back to Paine in the 18th century. Justice and freedom are keys to all of these arguments, e. g. that of Van Parijs, where if one looks at work as a fundamental resource, you should be free to take or not take a job.
There's so much literature on this—why not look into it?