Is a perfect sales tax actually regressive?

In raw dollars and in any other way you measure value. 

In raw dollars and in any other way you measure value. 

Not true. If everything becomes 25% more expensive, the same number of raw dollars is worth 20% less.

there is investment power money too

You only buy stocks so you can eventually spend the money. The dividends will have reduced purchasing power, so it's just kicking the can down the road.

Yes, there is inflation, and no, that doesn't change the fact that a sales tax is a regressive tax.

No, you buy stocks to make more money, and when you make more money then the sales tax you pay becomes an even lesser percentage of total earnings,

Yes, there is inflation, and no, that doesn't change the fact that a sales tax is a regressive tax.

A sales tax causes inflation, which impacts everyone's purchasing power by the same percent regardless of income.

No, you buy stocks to make more money, and when you make more money then the sales tax you pay becomes an even lesser percentage of total earnings,

Not really. With 20% income tax, I earn $100 and keep $80. I put it in the stock market and it doubles, giving me $160. With 25% sales tax, I earn $100, which would buy as much as $80 would without the tax. I invest the $100 in the stock market and it doubles. I now have $200, which buys as much as $160 would before the tax. Either way, someone who makes $100 would only get to buy 160 widgets after investing. With ten times as much, they'd get 10 times as many widgets, and 20% would be a ten times bigger loss.

I'm ignoring capital gains tax, but that's because that tends to work separately from income tax. A sales tax + capital gains tax would function the same as an income tax + capital gains tax.

sales tax percentage of total income is isn't equal, and hence, sales tax is regressive...the terms "sales tax", "progressive", "regressive", and "proportional" are explicitly defined economic terms, it's simple mathematics. What's the point of just changing definitions?

I'm ignoring capital gains tax, but that's because that tends to work separately from income tax. A sales tax + capital gains tax would function the same as an income tax + capital gains tax.

sales tax percentage of total income is isn't equal, and hence, sales tax is regressive...the terms "sales tax", "progressive", "regressive", and "proportional" are explicitly defined economic terms, it's simple mathematics. What's the point of just changing definitions?

I'm not changing definitions. Regressive taxes create a larger percentage burden on lower incomes. Sales tax doesn't. 

Even if you define it in terms of dollars spent, the rich person will eventually spend their money (it exists to be spent, after all), or someone who inherits it will. All that changes is when the tax is paid.

Yes, there is inflation, and no, that doesn't change the fact that a sales tax is a regressive tax.

A sales tax causes inflation, which impacts everyone's purchasing power by the same percent regardless of income.

Only expansion of the money supply causes inflation. We've been over this in another thread. I'll do it again, it's important.

it represents a larger percentage of the lower income, making it a regressive tax

the idea that all money is spent on sales taxable consumption

Only expansion of the money supply causes inflation. We've been over this in another thread. I'll do it again, it's important.

Then instead of inflation, "reduction in purchasing power"

I specified a sales tax that avoids loopholes. That would mean all consumption is sales taxable. There are loopholes for income tax, too, it's really not that different.

The federal government considers "basic groceries" to be zero-rated which means there is no GST or HST on those items. Whether or not you already know that there are no taxes on certain groceries, you might not know all of the food and drink products you don't pay tax on in Canada.

The federal government considers "basic groceries" to be zero-rated which means there is no GST or HST on those items. Whether or not you already know that there are no taxes on certain groceries, you might not know all of the food and drink products you don't pay tax on in Canada.

Which would make the sales tax progressive, the opposite of regressive.

it represents a larger percentage of the lower income, making it a regressive tax

The burden is reduced purchasing power, and that reduction is a consistent percentage.

the idea that all money is spent on sales taxable consumption

I specified a sales tax that avoids loopholes. That would mean all consumption is sales taxable. There are loopholes for income tax, too, it's really not that different.

Yes, inflation is expressed as a percentage increase, and no, that doesn't change the fact that a sales tax is a regressive tax.

The economics world just doesn't understand economics.

I get it, the mantra "money exists to be spent" is a principle of faith for you, but the idea that all money is spent on sales taxable consumption is an absurd fantasy

Yes, inflation is expressed as a percentage increase, and no, that doesn't change the fact that a sales tax is a regressive tax.

I'm not following. Is a sales tax not effectively inflating the price of all goods? If the burden of permanent inflation is proportional to income, why isn't the same true for a sales tax?

The economics world just doesn't understand economics.

I don't know if I'm missing something, but I've explained why the burden of a sales tax is proportional to income. It seems to me that you haven't explained why you believe it would be regressive.

I get it, the mantra "money exists to be spent" is a principle of faith for you, but the idea that all money is spent on sales taxable consumption is an absurd fantasy

Why is this an absurd fantasy? I'm open to hearing your opinions, but I have trouble following what your logic is, beyond potential loopholes, which I've already acknowledged that a tax ought to account for.

Money that is never used is worthless, since it doesn't serve the main purpose of money: spending. If I threw paint on 50% of your money and ruined it, you would be 50% poorer. You still have the same amount of bills, but your purchasing power has been cut in half since you can only spend half as much. That's kind of what a sales tax does in raising all prices by some percentage.

the concepts, definitions and mathematical formulas of modern-day economics

the concepts, definitions and mathematical formulas of modern-day economics

What concepts, definitions, and mathematical formulas supporting your position might there be?

So, read a book, find somebody besides me with an economics degree, it’s even as simple as using Google, they will all tell you that a sales tax is a regressive tax, and none of them will say except for “in real dollars” and not if “all money is meant to be spent”.

So, read a book, find somebody besides me with an economics degree, it’s even as simple as using Google, they will all tell you that a sales tax is a regressive tax

none of them will say except for “in real dollars” and not if “all money is meant to be spent”.

it seems like you're appealing to authority to shut down discussion and avoid addressing any of the points I'm bringing up.

So, read a book, find somebody besides me with an economics degree, it’s even as simple as using Google, they will all tell you that a sales tax is a regressive tax

I said that there are reasons an imperfect sales tax can be regressive, and a lot of those sources are combining income taxes with capital gains (even though it tends to function differently) or not addressing real dollars at all. Regardless, it seems like you're appealing to authority to shut down discussion and avoid addressing any of the points I'm bringing up.

You should at least be able to explain why my logic doesn't work.

none of them will say except for “in real dollars” and not if “all money is meant to be spent”.

I've seen some people make the argument I'm making, but again, I'm arguing based on how purchasing power works, not based on who agrees with me.

You still have not answered my question about what makes a sales tax a "perfect" sales tax, what is the difference.