Many legal contexts regard self employment equivalently as employment just as much as working for someone else, like job seekers allowance now Universal Credit. Appropriate adjustments are made to the process to correspond to each scenario, but with the aim of having the equivalent effect and access to support etc.
Standard visitors leave doesn't allow recourse to public funds, and sometimes exempts the visitor from liability for VAT on consumptions but it does allow one to conduct business while visiting. What is the distinction, if any at all, between the respective activities of self employment, and of conducting business?
Somewhat superficially, I suppose that conducting business may be negotiating and signing contracts, to sell things, buy things, produce things, etc. While self employment may more along the lines of working full time oneself directly rendering services to clients/customers like a massage therapist who either owns their own practice room or perhaps travels to people's homes. But the difference ultimately seems to be to be quite superficial and not at all fundamental to the nature of those activities and seems to me predominantly a question of how the activities are intentionally structured, described and framed as the line is much fuzzier then it may at first let on. For example, what if one spends their days performing work in the interest of some hoped-for eventual payoff but which isn't remunerated by the outside world on an hourly basis per se. Suppose someone is an author working daily on a book which work nobody may predict the hourly value of, but which the person does as they believe strongly in their own vision of the finished product and its prospects for success, and so they self-fund these activities whether composing the manuscript itself or corresponding with publishers to sell them on it, both of which may just as conceivably be delegated to someone else like a secretary or ghost writer who would be then doing the exact same things for a separate employer rather than themselves. Yet at the same time proposing disgusting and negotiating contracts with prospective publishing companies seems more akin to conducting business rather than self employment. Why can't the government just call anything at all "employing oneself to conduct business on one's own behalf"?
At that point, even calling up O2 customer service to negotiate one's phone bill could be called conducting one's own personal business. And why shouldn't it be?
Nonetheless, are the latter category of activities (self employment) permitted on a visitor's leave even while the right to work employer checking provisions would in practice never have much occasion to matter?