For, as anyone who tries to do practical work in the world will rapidly discover, there is a true and there is a false ideal of consistency. To pretend that in our complex modern society, where responsibilities are so closely interwoven, it is possible for any individual to cultivate "a perfect character," and stand like a Sir Galahad above his fellows—this is the false ideal of consistency which it is the first business of a genuine reformer to put aside; for no human being can do any solid work without frequently convicting himself of inconsistencies when consistency is stereotyped into a formula. On the other hand there is a true duty of consistency, which regards the spirit rather than the letter, and prompts us not to grasp foolishly at the ideal, like a child crying for the moon, but to push steadily towards the ideal by a faithful adherence to the right line of reform, and by ever keeping in view the just proportion and relative value of all moral actions. Let it be remembered that it is this latter consistency alone that has any interest for the Vegetarian. His purpose is not to exhibit himself as a spotless Sir Galahad of food-reformers, but to take certain practical steps towards the humanising of our barbarous diet system.
(Henry S. Salt, The Logic of Vegetarianism: Essays and Dialogues [London: The Ideal Publishing Union, 1899], 53-4 [italics in original])
Note from KBJ: Salt, bless his heart, is running together some things that ought to be kept separate. First is the question of whether one is living up to one's ideals. I, for example, am a demi-vegetarian. I eat chicken, fish, and eggs. I have had no other animal products (no beef, pork, lamb, or turkey, for example) since 1982. Am I a hypocrite? That depends on whether there are morally relevant differences between chickens and fish on the one hand and cows, pigs, and sheep on the other. (I believe there are.) But my diet is far closer than most people's to what I take to be the ideal. Surely that counts for something, morally. Salt seems to be saying that there are degrees of rightness. The ideal, even if one never achieves it, guides and inspires.
Second is the question of whether those who are not perfect have any business lecturing others. Think here of Thomas Jefferson, who, in 1776, wrote the following stirring words:
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their creator with certain unalienable rights, that among these are life, liberty, and the pursuit of happiness.
Jefferson owned slaves at the time he wrote these words. Does that mean he was not expressing profound moral truths? Does that mean nobody should take heed of what he said? Human beings are, and always will be, imperfect, morally and otherwise. If our standard is perfection, then everyone falls short of it and no distinctions can be made. Jefferson, an imperfect man like you, me, and everyone else, expressed profound and inspirational truths, leaving it to others to bring the world into conformity to them.
Note 2 from KBJ: There is a saying that captures Salt's point, if I understand him correctly. It is that the perfect is the enemy of the good. If nothing but perfection is acceptable, then, given human imperfection, nothing is acceptable. Turn it around: That something is acceptable implies that perfection is not the appropriate standard. We should strive for perfection, and each of us should encourage others to do better, but it would be foolish to expect anyone to achieve it.