Take an example from what you have just been saying.

Of three kinds of funerals, there is one which is too extravagant, another is too niggardly, the third in a mean; and you choose and approve and order the last without qualification.

But if I had an extremely rich wife, and she bade me bury her and describe her burial in a poem, I should praise the extravagant sort; and a poor miserly man, who had not much money to spend, would approve of the niggardly; and the man of moderate means, who was himself moderate, would praise a moderate funeral.

Now you in the capacity of legislator must not barely say 'a moderate funeral,' but you must define what moderation is, and how much; unless you are definite, you must not suppose that you are speaking a language that can become law.
CLEINIAS: Certainly not.
ATHENIAN: And is our legislator to have no preface to his laws, but to say at once Do this, avoid that--and then holding the penalty in terrorem, to go on to another law; offering never a word of advice or exhortation to those for whom he is legislating, after the manner of some doctors?
For of doctors, as I may remind you, some have a gentler, others a ruder method of cure; and as children ask the doctor to be gentle with them, so we will ask the legislator to cure our disorders with the gentlest remedies.

What I mean to say is, that besides doctors there are doctors' servants, who are also styled doctors.
CLEINIAS: Very true.
ATHENIAN: And whether they are slaves or freemen makes no difference; they acquire their knowledge of medicine by obeying and observing their masters; empirically and not according to the natural way of learning, as the manner of freemen is, who have learned scientifically themselves the art which they impart scientifically to their pupils.