Beauty : The characterization of a person as “beautiful”, whether on an individual basis or by community consensus, is often based on some combination of inner beauty, which includes psychological factors such as personality, intelligence, grace, politeness, charisma, integrity, congruence and elegance, and outer beauty (i.e. physical attractiveness) which includes physical attributes which are valued on a subjective basis.

Standards of beauty have changed over time, based on changing cultural values. Historically, paintings show a wide range of different standards for beauty. However, humans who are relatively young, with smooth skin, well-proportioned bodies, and regular features, have traditionally been considered the most beautiful throughout history.

A strong indicator of physical beauty is "averageness", or "koinophilia". When images of human faces are averaged together to form a composite image, they become progressively closer to the "ideal" image and are perceived as more attractive. This was first noticed in 1883, when Francis Galton, cousin of Charles Darwin, overlaid photographic composite images of the faces of vegetarians and criminals to see if there was a typical facial appearance for each. When doing this, he noticed that the composite images were more attractive compared to any of the individual images.

Researchers have replicated the result under more controlled conditions and found that the computer generated, mathematical average of a series of faces is rated more favorably than individual faces. Evolutionarily, it makes logical sense that sexual creatures should be attracted to mates who possess predominantly common or average features.

A feature of beautiful women that has been explored by researchers is a waist–hip ratio of approximately 0.70. Physiologists have shown that women with hourglass figures are more fertile than other women due to higher levels of certain female hormones, a fact that may subconsciously condition males choosing mates.

People are influenced by the images they see in the media to determine what is or is not beautiful. Some feminists and doctors have suggested that the very thin models featured in magazines promote eating disorders, and others have argued that the predominance of white women featured in movies and advertising leads to a Eurocentric concept of beauty, feelings of inferiority in women of color, and internalized racism.

The black is beautiful cultural movement sought to dispel this notion.

The concept of beauty in men is known as 'bishōnen' in Japan. Bishōnen refers to males with distinctly feminine features, physical characteristics establishing the standard of beauty in Japan and typically exhibited in their pop culture idols. A multi-billion-dollar industry of Japanese Aesthetic Salons exists for this reason.

Ugliness is a property of a person or thing that is unpleasant to look upon and results in a highly unfavorable evaluation. To be ugly is to be aesthetically unattractive, repulsive, or offensive. Like its opposite, beauty, ugliness involves a subjective judgment and is at least partly in the "eye of the beholder." Thus, the perception of ugliness can be mistaken or short-sighted, as in the story of The Ugly Duckling by Hans Christian Andersen.

People who appear ugly to others suffer well-documented discrimination, earning 10 to 15 percent less per year than similar workers, and are less likely to be hired for almost any job, but lack legal recourse to fight discrimination.

Although ugliness is normally viewed as a visible characteristic, it can also be an internal attribute. For example, an individual could be outwardly attractive but inwardly thoughtless and cruel. It is also possible to be in an "ugly mood", which is a temporary, internal state of unpleasantness, or may refer to the way one views themselves at the moment.

For some people, ugliness is a central aspect of their persona. Jean-Paul Sartre had a lazy eye and a bloated, asymmetrical face, and he attributed many of his philosophical ideas to his life-long struggle to come to terms with his self-described ugliness. Socrates also used his ugliness as a philosophical touch point, concluding that philosophy can save us from our outward ugliness. Famous in his own time for his perceived ugliness, Abraham Lincoln was described by a contemporary: "to say that he is ugly is nothing; to add that his figure is grotesque, is to convey no adequate impression." However, his looks proved to be an asset in his personal and political relationships, as his law partner William Herndon wrote, "He was not a pretty man by any means, nor was he an ugly one; he was a homely man, careless of his looks, plain-looking and plain-acting. He had no pomp, display, or dignity, so-called. He appeared simple in his carriage and bearing. He was a sad-looking man; his melancholy dripped from him as he walked. His apparent gloom impressed his friends, and created sympathy for him—one means of his great success."