The certain truth is that we, ourselves, experience pain and that it is bad. We have experienced the sufferings of this world, and we know how much a person can hurt. The uncertain truth is that other beings can also suffer. An absolute solipsist may not be convinced of this, but others will easily agree of the capacity of others to feel pain, and if they concur that pain is both intrinsically awful and the only thing that is awful in-itself, they will conclude that all beings capable of suffering have moral status, that they, if anything, deserve to be freed from the agonies of existence to the greatest extent possible, and though we live in this fundamentally bad state called biological existence, we as humans can use our reasoning to alleviate the plight of others – and this is what we should do above all else.
While any truth of science is based on induction, this truth is based on the “logical facts” of our experience. Even if this entire reality was a delusion (as long as we are all “real” fools being deluded by it) it would not change the moral truth of what I have said one iota. Now it is true that if all people are automatons, who cannot truly suffer but are “programmed” to shriek in pain when they are prodded, how Descartes saw animals for example, then it would make the uncertain truth false and the moral weight of (relative) moral egalitarianism and Negative Utilitarianism would fall apart. But to me it seems far-more certain that people are real than our reality is. Let me explain.
It is very-well true that everything our senses and most things are reason provides us is prone to error – therefore we can never with absolute certainty know hardly anything and what the Ancient Skeptics say of absolute knowledge’s impossibility is true. However, there is a distinction between saying that the senses can never tell us anything for certain about reality and saying that the senses cannot give us good grounds for believing in things in the world. The world may be false, but we can still know things about it whether or not the world is real or not. There is a difference between proclaiming all is perhaps not real and saying we know that this thing in the world is or isn’t. Both are not things we can ever know with absolute certainty, but I will hold we can know things about the world, such as whether or not there are people suffering in it, with far-greater “certainty” than we can know anything about reality in the absolute sense.
Though the world is an uncertain and complicated place, and therefore the conditions and specifics of Consequentialism are forever complex and uncertain to us, the facts of Negative Utilitarianism are more conclusive and can be known in the human head and heart more so than any of the sciences which are forever uncertain, for they are based on induction. Morality is more conclusive, definitive and absolute than science will ever be; it is also far-more useful and important to the human psyche or state-of-being, though both have their inter-related functions and value.
As long as we are on this Earth, we should do what we can to alleviate the suffering of others, prevent it, and be kind. This I know more than any other scientific law or property of any substance. To be good to others is to act on a knowledge more certain and more wise than any fact of our “reality” can ever be.