Like in real life, some people in Gaianar can wear more than one hat. While some might call it "moonlighting", in the Gaianar game system this is simply called a split-class. A character's class is like a full-time job. 

Most people in the real world, however, do not work two 40-hour jobs each week. Thus, a split-classed character cannot advance in both classes at the same rate. It is thus required that a split-classed character choose which class shall be primary and which shall be secondary. This is the equivalent of a real-world person having a full time job with part-time side work.
If a player chooses to be split-classed, then the earned experience is split 75% to the primary class and 25% to the secondary class.  A character who is split-classed at first level starts with –500XP instead of 0 XP. A character that is started with a single class but later desires to become split-classed can do so, but only when leveling up. The character must first pay 500 XP to take upon a second class, and paying this cost cannot drop the character by a level. Once these costs are paid, the new class starts at Level 1. The new class still grants the character the class-related “bonus skills” but taking on a second class does not allow the character to get all the starting skills for that class - starting skills are only gained once at the beginning of a character’s career.

The split-class character gains normal hit points and spirit points from the primary class and secondary class. Proficiency slot increases are reaped from the both classes as the character increases in level. The bonus skills for high Intelligence are granted only once, regardless of whether the character is a split class or single classed character. The character's saving throws, BAtCh, and combat matrices are based on whichever class has the more favorable value.

It should be noted that the two character classes must logically combine. In other words, a character class cannot be a Thief/Paladin because Paladins hold the law in high regard. An Investigator/Paladin, however would be acceptable since Investigators enforce laws. A character could not be a Cavalier/Protector because a Cavalier must wear metal armor, while a Protector must not. But aside from conflicting character class restrictions, the player is free to split-class her character any way she sees fit.