It may be nice to think of the law as common sense, but in most countries this is not the standard. Because 'common sense' changes, frequently and without cause

It may be nice to think of the law as common sense, but in most countries this is not the standard. Because 'common sense' changes, frequently and without cause. 'Common Sense' can be misleading in many situations -- medicine, law, business strategy, crime, etc. What is common sense to you about software may not be common sense to someone with no IT knowledge, and vice versa with regards to, say, how cheese is manufactured. The law adapts, sure, but it also tries to maintain order by being resistant to quick change. The fact that most of our legal system defaults to prior case law should say something about this. That said, I am not an attorney. I just know using common sense seems like an incredibly bad basis for determining legality.