> Light is not an abstraction, a contract is not an abstraction. 10 is not an abstraction, it is an ordinal [1].
It seems to me that all of those things very much are abstractions. They are not the utmost level of abstraction, but they are abstractions!
(Actually "a contract," which at first I thought was the clearest win, I'm now not sure about. On reflection, it seems like a concretization, turning abstract ideas of trust and reliability into concrete conditions under which the contract has or has not been met.)
It seems to me that all of those things very much are abstractions. They are not the utmost level of abstraction, but they are abstractions!
(Actually "a contract," which at first I thought was the clearest win, I'm now not sure about. On reflection, it seems like a concretization, turning abstract ideas of trust and reliability into concrete conditions under which the contract has or has not been met.)