Most employment contracts are 'contracts of service' not 'contract for service'. Servitude
We are serfs and the employers are our feudal lords, they swear fealty to the state 'Parliament'. Income tax, is the tax or protection money for providing you with protection in the guise of a contract.
Notice how income tax and NI contributions are only paid by those in employment.
Hence they can tax you. Clever buggersBecoming a serf
A freeman became a serf usually through force or necessity. Sometimes freeholders or allodial owners were intimidated into dependency by the greater physical and legal force of a local baron
. Often a few years of crop failure, a war or brigandage might leave a person unable to make his own way. In such a case a bargain was struck with the lord. In exchange for protection, service was required, in payment and/or with labour. These bargains were formalized in a ceremony known as "bondage" in which a serf placed his head in the seigneur's hands, parallel to the ceremony of "homage" where a vassal placed his hands between those of his lord. These oaths bound the seigneur to their new serf and outlined the terms of their agreement.  Often these bargains were severe. A 7th century Anglo Saxon "Oath of Fealty" states "By the Lord before whom this sanctuary is holy, I will to N. be true and faithful, and love all which he loves and shun all which he shuns, according to the laws of God and the order of the world. Nor will I ever with will or action, through word or deed, do anything which is unpleasing to him, on condition that he will hold to me as I shall deserve it, and that he will perform everything as it was in our agreement when I submitted myself to him and chose his will." To become a serf was a commitment that invaded all aspects of the serf’s life.
Moreover, serfdom was inherited. By taking on the duties of serfdom, serfs bound not only themselves but all of their future heirs.The serf's duties
The usual serf (not including slaves or cottars) paid his fees and taxes
in the form of seasonally appropriate labour. Usually a portion of the week was devoted to plowing his lord's fields (demesne), harvesting crops, digging ditches, repairing fences, and often working in the manor house. The lord’s demesne included more than just fields: it included all grazing rights, forest produce (nuts, fruits, timber, and forest animals) and fish from the stream; the lord had exclusive rights to these things.
The rest of the serf’s time was devoted to tending his or her own fields, crops and animals in order to provide for his or her family. Most manorial work was segregated by gender during the regular times of the year; however, during the harvest, the whole family was expected to work the fields.
Specifics of serfdom varied greatly through time and region. In some places, serfdom was merged with or exchanged for various forms of taxation.http://en.wikipedia.org/wiki/Serfdom#Freemen