Both parsimony and plentitude are well worn terms (with relatively precise meanings) within the world of science ---- but buttressing each scientific term are two long standing but wildly varying philosophies of life that we all must chose between.
The two philosophies agree just once : in both accepting that current - readily observable - reality does appear to be very dynamic and complex.
But only one philosophy accepts that this vision of ever-dynamic complexity is probably as about as accurate a version of reality that we humans are ever likely to get.
The other philosophy derides that view as a 'false consciousness' and craves to find a much simpler , more predictable, stable and controllable reality buried somewhere deep in that heaving surface morass.
I think it is fair to say that the Era of Modernity (1875-1965) chose the philosophy of parsimony and the Era of Commensality (1965- ?) has chosen the philosophy of plentitude.
For parsimony sees reality as akin to thermoset polymers and says that there are always winners and always single best solutions.
And that moreover we can readily determine them and congeal them for all time.
While plentitude sees reality as rather like thermoplastic polymers and says there are no winners or losers - just ever-plastic life in all its complexities.
It says that history has shown we haven't had much happiness when we set out to exalt the winners and to holocaust the losers....