David, here are some links to some of my comments and my diary on BMG that makes the same arguments you are now making regarding the SJC’s interpretation of Article 44. When I made these points last year, I was frustrated that you (and christopher) simply dismissed them by citing Article 44, without considering my contention that Article 44 has been interpreted wrongly and we should ignore that interpretation. It’s not too late to add a link now, since it was on BMG and you own it anyway now.
Article 44 makes a reasonable distinction between income derived from property being able to be taxed higher than income not derived from property that I think is itself a graduated tax in spirit, not on people with higher income but on people with higher amassed wealth. The question is if the person’s income is due to their property, then tax it higher. Thus the Harvard professor in the Raymond SJC case might just be deriving their salary due to their owning a contract such as tenure that is tied to the property known as Harvard University, but another teacher earning the same amount but without a contract granting them a share of a limited resource like a land-grant University’s reputation and campus and property is earning it purely on their teaching ability, so should be taxed less. The idea is to compensate for the tendency for the rich to get richer while the poor get poorer. The rich, obviously, are those with property, and when they use their property to earn their income, they have an advantage over people with out that property, so tax them more. One could even say that income derived from a college degree should be taxed higher than someone earning the same salary but without a college degree. Though of course you can’t just buy a degree (supposedly).