When the thirty-three trapped Chilean miners were entombed in a dark cave with their futures uncertain, they were playing out a timeless plot of isolation and rescue reminiscent of Lord of the Flies or The Flight of the Phoenix. Except in this ordeal they turned not to struggles of power and control, but to reasonable principles quite similar to Kant's categorical imperative.
What emerged early on was a rigid set of rules or categoricals. Only eat every other day; portions absolutely equal; no-one eats until everyone has received their portion. They consented together to treat each other with absolute dignity and equality as the only recognizable way to survive an ordeal whose length and end was uncertain. Each consented to engage in a collective solidarity - and solidarity became the catch-word. As with Kant, it was "duty for duty's sake" where the duty was to treat each other as an end in themselves, and to accept the logic of universalizing their individual behaviour - what is best for you is also best for me, what is best for me is best for you.
It may be that the principle of universalisability, or the golden rule approximation "do to others as you would have them do to you", is actually a universal and objective principle, as Kant argued it was. As an empirical fact, it occurs in every major world religion, and quite a lot of minor ones. They are available for inspection on a fascinating website.
Kant argued that the principle which he called the categorical imperative was something we arrive at a priori, before experience - we fall back on it as it were by the nature of the way our minds work when we start to reason morally because moral thinking belongs to the world of ideas alone - practical reason he calls it - a world where we intuitively grasp concepts of space, time and number.
As free beings, recognizing our fellow human beings, how do we naturally behave? Do we slip back into the law of the jungle - the realm of the Lord of the Flies - or do we create a mini society by all casting a vote as autonomous (free) human beings, taking the most reasonable course of action for a higher good? Of course, other plots have finished differently, and we don't know how this would have ended had the miners remained entombed, and the food run out, but it is encouraging to those who think ethics is reflected in the way all of us reason, that in this case, crisis produced a common agreement on the importance of absolutes.