It all depends for what the optional part applies. If I run my car at high speed, the fuel consumption is lower than when I am driving in heavy traffic in town. The optional speed is thus a high one. ShouLd taxation be made high too, because its collection then becomes more efficient? The optional tax as I see it is the tax that is the easiest to calculate and to least expensive to collect. We are far from this situation today and in fact there is a much simpler and more just way of tax gathering that should be applied at the same time as the taxes are optimized in this way. The advantage of doing this are not only the tendency towards greater economy of collection. I refer to the taxation of land values, where the ownership of the sites are clear and also their value is easy to determine and publish. Then the tax is in fact some of the economic rent on the unimproved site due to its position and possible natural resources. This tax would boost the economic growth from both ends. The cost of production would fall, due to the freeing of unused land and lower rents. It would also enable production-based taxes such as on incomes and VAT to be reduced without the national income changing, which would leave more spending power in the hands of most of the low and middle income consumers. This tax is also a fair tax because it takes from the land holders what opportunity they are taking from the general public in land utility. The value of the land is largely due to the population density and (taxed) investment by the city councils on which no yield is normally drawn. But investment should yield income and this money is is what effectively goes into the pockets of the land lords when they speculate in land for no necessary purpose except their own greed. TAX TAKINGS NOT MAKINGS.