selections from On Moral Ends:
By claiming that the senses alone decide that pleasure is good and pain evil, Epicurus grants more authority to the senses than the law allows us when we sit in judgement on law-suits. We can only judge what falls within our jurisdiction. Judges tend when announcing their verdict to add the phrase, “if it is within my jurisdiction” –an empty phrase, since cases that are outside their jurisdiction are not brought within it by this utterance. What are the senses competent to judge? Sweetness and bitterness, smoothness and roughness, proximity and distance, rest and motion, squareness and roundness. Hence a fair verdict can only be delivered by reason, assisted in the first place by knowledge of things human and divine, which is rightly called wisdom, and in the second place by the virtues, which reason puts in charge of every domain, whereas you want them to be a servant ministering to pleasure. After consulting these advisors, reason shall deliver its first decision: there is no place for pleasure either to claim sole occupancy of the throne of the supreme good that we are investigating, or even to sit side by side with morality. The same verdict will be delivered on freedom from pain.
We must investigate where that supreme good that we want to discover is to be found. Pleasure has been eliminated from the inquiry, and pretty much the same objections hold against those who maintained that the ultimate good was freedom from pain. Indeed no good should be declared supreme if it is lacking in virtue, since nothing can be superior to that.
Ignorance of the supreme good, however, is necessarily equivalent to ignorance of how to plan one’s life. And this may take one so far off course that one loses sight of any haven to provide shelter. Once, however, we understand the highest ends, once we know what the ultimate good and evil is, then we have a path through life, a model of all our duties, to which each of our actions can thereby be referred.
In fact it is at precisely this point of inquiry into the supreme good that philosophical controversy rages. The origin of the whole dispute about the highest goods and evils, and the question of what among them is ultimate and final, is to be found by asking what the basic natural attachments are.
So it turns out that there is a difference of opinion over the first principles of nature corresponding exactly to the dispute over the highest goods and evils.
1. In what way do first principles about the nature of things lead to disagreements about the highest good?
2. What is the consequence of ignorance about the highest good?
3. Why can't the senses tell us what is the highest good?