(Based on the assumption that human beings are subject to evolution like any other creature inhabiting the earth)
Our behaviour is controlled by evolutionary forces.
Love, good taste, originality, art, charity, loyalty, principles are all geared towards making us and our species survive and thrive into the future.
This straightforward goal of evolution is not recognized by humans when in love, producing art, helping the poor and so on.
This ignorance towards this realisation is also necessary for evolution.
If you realise that everything you do, like, love, want, need, care for, and believe in is purely for the propagation of your genes and your species, you may begin to question these acts.
What is there to gain by evolution-based acts if I will not survive more than 100 years? If my children and grandchildren won’t survive more than 200 years from now? This is a dangerous question.
When you come to the point of asking this question, you can see that love, good taste, originality, art, charity, loyalty, principles are all illusions.
Then you come to the most critical point of all.
You realize that your life and actions are arbitrary and are only meaningful because of the value system you have, given to you by evolution, to assist in the propagation of your genes and your species.
Then, you choose.
You choose either to keep those arbitrary values and live on the way you were living according the plan of evolution or go insane (because there is no other guide to action besides evolution).
At this point, you choose love, good taste, originality, art, charity, loyalty, principles…
Your intelligence, although it helped you get to the point of realizing this, is, in essence, no better than the instinct of a bacteria or a virus, species that have survived and thrived for millions of years, because you are a complete slave to evolution just like the microbes.