fig-philosophy not in output.

[lluang]

Figure 11.1.1 (Philosophical foundations of SLR) did not come out and leads to a broken link in section 11.1.1. pg. 227 (IPSUR, 2nd edition June 6, 2014)

The relevant code is in IPSUR.org lines 13543. Unfortunately, I do not know org-mode so I do not know where the mistake may be (the R code works)

https://github.com/gjkerns/IPSUR/blob/master/IPSUR.org#L13643