Which preposition to use with abstractness

of Occurrences 6%

This is not contradicted by the fact that mathematical, astronomical, and physical reasonings may, when complex, be carried on more suecessfully by the employment of signs; because in these cases the signs themselves accurately represent the abstractness of the relations.

per Occurrences 1%

Abstractness per se seems to have a touch of ideality.

Which preposition to use with  abstractness