[Principled]

{Light bills]...they are easily calculated because you know all the variables in the equation.

That's not right. You don't know the amount of usage. Also, in some places, the kwh usage changes depending on usage level. So besides not knowing the value to use for the variables, you don't know which variables will be used in the calculation of your light bill.

How is it again that the light bill is an expense paid from sales revenue, but income taxes aren't paid from sales revenue? BTW, if the money to pay for income taxes doesn't come from sales revenue, where does it come from? Of course profits come from sales revenue too.

[justshutupandtakeit]

You keep confusing independent variables and dependent variables in the Tax equation. Profit is the independent variable. Income tax is the dependent variable.

In the Profit equation profit is a dependent variable while revenues and costs are the independent variables.

P= R-C, T= T(P) without getting much into math one cannot solve an equation which is using a variable as both an independent and dependent variable. Perhaps one more mathematically oriented can explain it better after all it has been 30+ years since I studied these matters intensely.

Earlier economic theory postulated three factors of production: land, labor and capital. Marx divided capital into fixed and floating (the wage fund) more recent theorists dropped his innovation and added Human Capital into the factors. Income tax compliance costs are in the labor category. The income tax itself is in none of the three hence is not a cost.