Silent enim leges inter arma. - Cicero

Magistratum legem esse loquentem, legem autem mutum magistratum

Denique isto bono utare, dum adsit, cum absit, ne requiras: nisi forte adulescentes pueritiam, paulum aetate progressi adulescentiam debent requirere. cursus est certus aetatis et una via naturae eaque simplex, suaque cuique parti aetatis tempestivitas est data, ut et infirmitas puerorum et ferocitas iuvenum et gravitas iam constantis aetatis et senectutis maturitas naturale quiddam habet, quod suo tempore percipi debeat.

There is also a tradition about Socrates. He liked walking, it is recorded, until a late hour of the evening, and when someone asked him why he did this he said he was trying to work up an appetite for his dinner.