> no definitions, "We take mathematical structure to mean the identification of general properties which are instantiated in particular situations as relations

> no definitions, "We take mathematical structure to mean the identification of general properties which are instantiated in particular situations as relationships between elements or subsets of elements of a set." In case you missed it (it's the first sentence of the abstract), it's also repeated as the first sentence of the paper. Compare to, say, a paper published by a well-respected famous mathematician: https://www.renyi.hu/~p_erdos/1989-39.pdf https://www.renyi.hu/~p_erdos/1989-39.pdf