This acted as a justification for one's judgements about the thing being perceived. Enargeia is characterized as sensation of an object that has been unchanged by judgments or opinions and is a clear and direct perception of that object. An individual's preconceptions are his or her concepts of what things are, e.g. what someone's idea of a horse is, and these concepts are formed in a person's mind through sensory input over time. When the word that relates to the preconception is used, these preconceptions are summoned up by the mind into the person's thoughts. It is through our preconceptions that we are able to make judgments about the things that we perceive. Preconceptions were also used by Epicureans to avoid the paradox proposed by Plato in the Meno regarding learning. Plato argues that learning requires us to already have knowledge of what we are learning, or else we would be unable to recognize when we had successfully learned the information. Preconceptions, Epicureans argue, provide individuals with that pre-knowledge required for learning. Our feelings or emotions (pathê) are how we perceive pleasure and pain. They are analogous to sensations in that they are a means of perception, but they perceive our internal state as opposed to external things. According to Diogenes Laertius, feelings are how we determine our actions. If something is pleasurable, we pursue that thing, and if something is painful, we avoid that thing. The idea of "presentational applications of the mind" is an explanation for how we can discuss and inquire about things we cannot directly perceive. We receive impressions of such things directly in our minds, instead of perceiving them through other senses. The concept of "presentational applications of the mind" may have been introduced to explain how we learn about things that we cannot directly perceive, such as the gods. Ethics Epicureanism bases its ethics on a hedonistic set of values, seeing pleasure as the chief good in life. Hence, Epicurus advocated living in such a way as to derive the greatest amount of pleasure possible during one's lifetime, yet doing so moderately in order to avoid the suffering incurred by overindulgence in such pleasure. Epicurus actively recommended against passionate love, and believed it best to avoid marriage altogether. He viewed recreational sex as a natural, but not necessary, desire that should be generally avoided. Since the political life could give rise to desires that