Does Singer's principle have any validity and credibility: "if it is in our power to prevent something bad from happening, without thereby sacrificing anything of comparable moral significance, we ought, morally to do it"?
Singer’s moral principle is strong in its premise but it is also somewhat vague in specificity. The empirical assumption that he proposes is that “something bad” should be prevented from happening as long as we do not allow for “some other bad thing” to happen in the process of this prevention. Yet, that “bad thing” is subject to moral interpretation; what is “bad” to someone is not the same to others.
The basis to reject this principle would be the interpretation of what is “bad” and what is “good”. Think about the September 11 attacks. What were the terrorists thinking that day? They thought that they were doing a good thing by bringing down the airplanes, crashing on the towers, and killing over 2,500 Americans in the name of their beliefs. They thought that it was in their power to prevent something bad from happening: they wanted to destroy the American way of life, which they thought to be a “bad thing”. They also felt it was morally correct to do this by taking their own lives, which is a sign of ultimate submission and determination. That abomination would have complied completely with Singer’s principle. This is the reason why, unless there is specificity, there could be grounds to reject the principle.
Singer’s resembles Mill’s idea of Utilitarianism in that both premises share naturalistic and equivocation fallacies. The fallacy being the assumption that one thing must equal another. In this case, just because something is happening you have a moral obligation to prevent it as long as what you are doing to prevent it is bad as well. Already, we have seen that there are flaws to that premise if it lacks specificity. Utilitarianism is equally flawed in that respect. It makes the assumption that the purpose of life is the pursuit of happiness and that every action we make must satisfy a purpose (must be useful). However, this is not always the case and we do not always need to seek for pleasure nor are obligated of living a purpose-driven life. It makes you are more fulfilled person to do so, but one cannot just assume that things lacks a gray area.