There's a well-established principle in politics, going all the way back to ancient Greece: for a just, stable and equitable society, you need to ensure that state power is divided into separate entities: executive, legislature, and judiciary.
The idea is that each entity keeps an eye on the other two, and any abuse of power is kept in check. Judges hold parliaments and presidents to account; parliaments hold governments to account.
In the UK, for example, the Home Office is regularly in trouble with the courts, both domestic and European, over immigration and anti-terrorism laws. Ministers and MPs don't much like it, but the principle is a sound one: even law-makers have to be told when they're breaking the law.
Which brings me to Pakistan, Paraguay, Egypt and Kuwait. They're not countries which could normally be said to have much in common, but over the past week alone, in each one of them we have seen this theory of separation of powers in action.
Pakistan: the supreme court told the prime minister he is not legally allowed to remain in office, since he has been held to be in contempt of court for refusing to reopen investigations into corruption allegations against the president. (Sub-plot: as soon as the ruling party named a prime ministerial replacement, an arrest warrant was issued against the new chap, so now they've had to come up with yet another name.)
Paraguay: later today, the Senate is due to start impeachment proceedings against the president, Fernando Lugo, who is held responsible for the deaths of 17 people when police tried to evict about 150 farmers from an estate owned by a prominent politician. His allies call the impeachment proceedings "an institutional coup".
Egypt: where do we start? The supreme constitutional court has dissolved the recently-elected parliament, on the grounds that a third of the seats were improperly contested; the ruling military council has issued a "constitutional declaration" awarding itself sweeping legislative powers; and the election commission has delayed announcing the results of the presidential election because it's still "examining complaints".
And finally, Kuwait, where the constitutional court has dissolved parliament on the grounds that it was elected unconstitutionally because the decree authorising the election had been drawn up after the resignation of the cabinet.
Oh, all right, perhaps you've got the appetite for just one more: in Washington, the House of Representatives Oversight and Government Reform Committee has voted to charge the attorney-general, Eric Holder, with contempt of Congress after the Obama administration withheld documents related to a failed gun-running investigation.
Isn't it wonderful, seeing consitutional theory in action in so many different countries -- in each case, one branch of government holding another to account?
Well, perhaps it is, and there again, perhaps it isn't. I'll leave you to judge the merits of each case, but it won't surprise you to learn that everywhere there are allegations of political machinations and hidden plots.
In Paraguay, there are the allegations of an "institutional coup"; in Egypt, they talk of a "soft coup". In Washington, the White House has accused the Republicans on the Congressional committee of "political theatre".
If you're a conspiracy theorist, you may argue that it's hardly a coincidence that in both the Egyptian and Kuwaiti parliaments, Islamists were a growing or dominant force, much to the alarm of the traditional ruling classes.
In Paraguay, you might argue that President Lugo is facing impeachment because his rivals still can't accept his election victory four years ago when he ended more than 60 years of rule by the right-wing Colorado party.
And in Pakistan, you might argue -- as many do -- that the enforced resignation of prime minister Yousuf Raza Gilani owes as much to long-standing personal animosity between the chief justice Iftikhar Muhammad Chaudhry and President Asif Ali Zardari as it does to consitutional principles.
So what are we left with at the end of this unusually turbulent week, even by recent standards? A world in which presidents and prime ministers are pushed hither and thither, in which "deep states" (hidden power structures, in other words) are accused of seeking to subvert the popular will.
It's a world in which more and more people are given the opportunity to vote for presidents, prime ministers and parliaments, and yet where suspicions remain that somehow the same people remain in power, regardless of who wins the elections.
It doesn't seem ideal by any means, but I don't have any answers. Do you?