What is the underlying concept governing the generally accepted accounting principles pertaining to recording gain contingencies?

The answer is "conservatism".

Conservatism refers to any political reasoning that favors convention (in the feeling of different religious, social, or broadly characterized convictions and traditions) despite outer powers for change, and is incredulous of proposition for radical social change.

Hamlet's fourth soliloquy is probably his most famous one - "to be or not to be."it is rather different from his previous soliloquies because now he is contemplating something that didn't come up before - suicide. he is thinking whether it is worth it to fight to find his father's murderer when in the end all of them are going to die, so why not die sooner than later. he is contemplating if he should go on fighting or just kill himself and end it all, which is why this soliloquy in particular is rather depressing, hesitant, and gives a deeper insight into hamlet's madness.