Doesn't it have to be "persist in full force"? I haven't seen "persist" used as a transitive verb.
28)In prehistoric times, any attempt to harness nature meant forcing nature against her will. Nature had to be challenged, usually with some form of magic or by means that were above nature ―that is, supernatural. Science does just the opposite, and it works within nature’s laws. The methods of science have largely taken away reliance on the supernatural ―but not entirely. The old ways persist full force in primitive cultures. They even survive in technologically advanced cultures too, sometimes ③disguised as science. This
'Full force' here is not intended as a nominal object, but rather as an adverbial objective, i.e. a prepositional phrase with ellipsis of the preposition.
In some cases, such as 'every Tuesday', (rather than ?on every Tuesday), the ellipsis is virtually mandatory. In others, such as here, it is simply a slightly informal-sounding option.