Free will
Free Will enables the Sims to move without being directed by the player. They can move and do certain actions without being told to, if it is turned on in the settings. Most of these actions are in connection with their needs, they do others just for fun. What Sims do as a result of Free Will will not always be the best or most rational choices they could make. For example, a Sim who has just enough time to eat and shower before the carpool comes may decide to play on the computer.
Some things that Sims do in Free Will won't occur when Sims are in a very bad mood.
Some interactions can't be directed, but can happen autonomously. For example, a Sim can "Look out" a window or "Check out" a new object, but can't be told to do so without testingcheatsenabled activated. On the other hand, Sims will not do certain things unless directed to by the player, even if Free Will is enabled. Some examples are looking for a job; asking another Sim to move in; proposing engagement or marriage; and WooHoo.
By default, Free Will is on in every game. In most games, it can be enabled or disabled from the "Game Options" menu—but The Urbz: Sims in the City and The Sims 2 Castaway are exceptions to this. Beginning with The Sims 2, it is set for each lot, and will be on when a family moves into a new lot.
Even if Free Will is disabled, Sims may still move without player direction if it is a life or death situation.
The Sims
Free Will can be enabled or disabled, and is enabled by default. Unlike later games in the series, Free Will in The Sims is a global option, even though it can only be enabled or disabled while playing a lot. If Free Will is disabled, it will be disabled for all lots in all neighborhoods. If Free Will is disabled, selectable Sims will not do anything without player direction, though visitors and pets[Unleashed] will always have Free Will.
The Sims (console) and The Sims Bustin' Out
Free Will is similar to The Sims.
The Sims 2
Free Will is no longer global, and can now be enabled or disabled for each individual house. Free Will is more advanced than in The Sims. Sims will generally make better choices, but may decide to do things such as make a very filling meal when they're only slightly hungry. Sims may make Free Will choices even while the player is looking though an object's menu.
With the Pets expansion pack, Sims will frequently interact with pets as a result of Free Will, and pets may autonomously seek to interact with Sims.
Sometimes if the Sims are enemies, they may use negetive socials such as Slap if Free Will is enabled.
The Urbz: Sims in the City
The Urbz: Sims in the City does not have a Free Will option and Free Will cannot be disabled. The Sims 2 restored this option and allows the user to disable Free Will.
The Sims 2 (Console)
The ability to disable Free Will, which was removed in The Urbz: Sims in the City, is restored. Free Will is similar to The Urbz and earlier console games.
The Sims 2 Pets (Console)
Free Will is similar to, and behaves like, Free Will in The Sims 2. However it has a timer when to enable free will, ex. 2 Min means that free will will be enabled after 2 minutes. [clarification needed]
The Sims Stories series
Free Will in The Sims Stories is similar to Free Will in The Sims 2, and has the same features.
Note: In The Sims Castaway Stories Free Will can be disabled; unlike The Sims 2 Castaway, in which Free Will cannot be disabled and the user is only allowed to set the the Time
The Sims 2 Castaway
Unlike its predecessors The Sims 2 Pets and The Sims 2, The Sims 2 Castaway does not allow the user to disable Free Will, but it can be configured.
The Sims 3
The Sims 3 not only allows the player to turn Free Will on and off, but now has varying levels of High, Medium, Low, and Off. Free will does not only keep a Sim sustained in life with almost no player interaction, but will also choose interactions based on the Sim's traits, favorites, and how they are compatible with other Sims in socialization. For example, if a Sim has the Green Thumb trait, they will autonomously garden and take care of their plants and even talk to them. If a Sim knows the recipe for their favorite food they will be more likely to cook it than any other dish. Sims will give positive reactions and interactions to Sims who are compatible in traits and the opposite with non-compatible traits. With Story Progression on, this free will is more noticeable with other Sims not currently controlled by the player. Sim children will even do their homework if the free will is high enough. When free will is set to off, then Sims react autonomously only in order to save their lives.