Maybe consider the relationship between consequentialism (theory) and deontology (practice): the rules of the latter can be considered pre-calculated shortcuts to the former. For example, “do not kill” and other commandments are widely applicable shortcuts for most real-world consequentialst calculations, though they obviously fail in some cases. An example from religious ethics: you ought to donate some of your income to charity (through church), but how much? A tithe (1/10) of your material and/or financial revenue is a rule that makes it workable in practice in many cases, without an undue burden.
Of course, with time the rules of deontological ethics tend to become “imperatives” due to lost purposes, and “practice” becomes “theory”.
Maybe consider the relationship between consequentialism (theory) and deontology (practice): the rules of the latter can be considered pre-calculated shortcuts to the former. For example, “do not kill” and other commandments are widely applicable shortcuts for most real-world consequentialst calculations, though they obviously fail in some cases. An example from religious ethics: you ought to donate some of your income to charity (through church), but how much? A tithe (1/10) of your material and/or financial revenue is a rule that makes it workable in practice in many cases, without an undue burden.
Of course, with time the rules of deontological ethics tend to become “imperatives” due to lost purposes, and “practice” becomes “theory”.