What is the ruling on working with a private car as a taxi to improve one's livelihood, given that the state prohibits this without a license?

There is no harm for a person to work with his private car as a taxi to improve his living standard, even if the state prohibits it without a license. It is not permissible for the state to prevent people from doing so, as it cuts off their livelihoods, unless there is a legitimate and recognized benefit or a prevention of corruption.

It is not permissible for any authority to generally prohibit some permissible acts or to make their performance dependent on its permission. Rather, the Muslim ruler may temporarily obligate or prohibit an individual permissible act, provided that it is not general for all people, and that it is specific to a certain situation according to certain regulations:

1. If performing the permissible act leads to harm or something forbidden, then the ruler may prohibit it. 2. If the permissible act relates to the state's private affairs, such as its army's affairs and its employees. 3. Organizing public facilities and matters in which Muslims share. 4. Implementing communal obligations (fard al-kifaya) entrusted to the state.

Therefore, it is not permissible for the state to prohibit the permissible or obligate its performance, or restrict it with its permission as a general legislation. Rather, it may intervene by prohibiting or obligating in some individual permissible acts in specific cases, with the aim of achieving a legitimate objective and according to the mentioned regulations.