Regardless of what ethical intuitions and beliefs a person has, one of the surest ways to sour a person in their eyes is to reveal their hypocrisy. Hypocrisy is something that is repulsive to anyone who cares about integrity because it is that one thing that by definition breaks from having ethical integrity. A man can boldly declare that he is an agent of Satan, and it is his ethical duty to torture as many puppies as possible. And another can be a huckster for God, collecting millions of dollars from the gullible and credulous, condemning homosexuality, and then later be charged with possessing child pornography of underage boys. Though the former is more harmful to agents capable of feeling pain, he also possesses more integrity than the man who gets rich selling “branded religion” and doesn’t believe in his product.
Now it should be noted that there is a difference between hypocrisy and moral weakness. All religions create harsh rules of conduct for people to live by. There is a difference between legitimately attempting to live according to a code and failing, and never trying and yet espousing it as “gospel truth” or condemning others when they stray from this allegedly self-evident and necessary path. Everyone hates a hypocrite and yet everyone has been a hypocrite in one aspect of another. Schopenhauer speaks of the trait of people despising when their autonomy or dignity is violated, and yet when we have the option to disregard others and treat them with the same apathy its done instinctually. This deals with the Egoism that is at the heart of a great deal of our nature.
If we cannot deduce any ethical knowledge, can we still salvage the concept of hypocrisy? In one way yes, in another no. We cannot strictly because we cannot outright dismiss Ethical Egoism. Egoism does away with hypocrisy because it’s the normative stance that proclaims, “anything that furthers my will.” If I can steal a hundred dollars from someone, and then convict someone who commits the same ill against me then one charge me with hypocrisy, but if the ought of life is, “anything that furthers my will” then Egoism surpasses treating others as you would like to be treated. One could claim that Egoism claims a “universal Egoism” where all human beings should promote either their own self-interest or their own desires. And then one could attempt to argue that there can still be a sort of hypocrisy that is wrong, where one pursues their own interest but argues against others doing the same. However, if “anything that furthers my will,” is the true law of a man’s heart, then to convince others of different ethical systems or of moral compulsions is more reasonable than to tell people they shouldn’t help you and should only think of themselves. This is why con men get into religion, not because religion is itself a con, but because morality can always be exploited by Egoists to benefit themselves.
Hypocrisy can still be argued against if we assume that ethics may be dependent on context but is not dependent on agent. Though we cannot ground in reason that we ought not be hypocrites it seems reasonable to find it unattractive because we find ethical integrity and fortitude attractive. We cannot establish that we ought to, either find it attractive or have what we find attractive, but what we can say is that integrity is both desirable for the sake of our species and for its own sake. We are hard-wired to dislike hypocrisy, and the concept of hypocrisy is a necessary concept if we are to pursue an ethic that is dependent on the quality of the character, the rule or the consequences all of which hold that an any particular agent is subject to the law of the general.