The ascendant ( or As), or rising sign, is the zodiacal sign and degree that was ascending on the eastern horizon at the specific time and location of an event. According to astrological theory, celestial phenomena reflect or determine human activity on the principle of 'as above so below'. Thus astrologers believe that the ascendant signifies a person's awakening consciousness, in the same way that the Sun's appearance on the eastern horizon signifies the dawn of a new day. Due to the fact that the ascendant is specific to a particular time and place, it signifies the individual environment and conditioning that a person receives during their upbringing, and also the circumstances of their childhood. For this reason, the ascendant is also concerned with how a person has learned to present him or herself to the world, especially in public and in impersonal situations. In some circumstances, it can therefore function as a shield or mask to guard a person's real nature - in other words the 'defense mechanism' every person has to cope with unfamiliar or uncomfortable situations. The ascendant also has a strong bearing on a person's physical appearance and overall health.