Destiny refers to the concept of life as a predetermined sequence of events.
The degree to which destiny is predetermined is heavily contested. There are two main schools of thought:
- Destiny as fate implies a fixed sequence of events that is inevitable and unchangeable, where an individual has no choice and must embrace their fate.
- Destiny as a choice suggests that individuals define their own destiny, by choosing different paths throughout their life.
In the future, a malevolent AI known as Skynet becomes self-aware and triggers the nuclear holocaust of Judgment Day. The humans create a rebel Resistance organization led by John Connor that succeeds in almost defeating Skynet. To avoid this, Skynet sends several Terminators into the past:
- A T-800 to kill Sarah Connor, John Connor's mother (The Terminator)
- A T-1000 to kill John Connor (Terminator 2: Judgment Day)
- A T-X to kill John Connor's lieutenants (as in the Resistance), and John himself, if possible (Terminator 3: Rise of the Machines).
- A T-888 to kill John Connor, and possibly Sarah, too (Sarah Connor Chronicles)
To counter each threat, the Resistance sends three entities into the past as well:
- A human (Kyle Reese) to protect Sarah Connor (The Terminator)
- Another T-800 to protect John Connor (Terminator 2: Judgment Day)
- A T-850 to protect John Connor and his lieutenants in the Resistance (Terminator 3: Rise of the Machines)
- A unknown type of Terminator to protect John Connor and Sarah Connor (Sarah Connor Chronicles)
Sarah Connor also tries to prevent the seemingly fated emergence of Skynet and Judgment Day, by preventing the research that becomes Skynet (Terminator 2). But despite this, Skynet and Judgment Day continue to be only delayed, suggesting a certain bias towards predestination in the series.
- John Connor: (message sent through Kyle Reese) "Thank you, Sarah, for your courage through the dark years. I can't help you with what you must soon face except to say that the future is not set. You must be stronger than you imagine you can be. You must survive, or I will never exist."
- The Terminator
- John Connor: No fate... No fate but what we make... My mother taught me this... I mean, I made him memorize it as a message to HER... Never mind. Okay, the whole thing goes "The future is not set. There is no fate but what we make for ourselves."
- Terminator: She intends to change the future.
- John Connor: Yeah, I guess. (shouting) Oh, shit!
- Terminator: Dyson.
- John Connor: Yeah, It's gotta be... Myles Dyson. She's gonna blow him away!
- Terminator 2: Judgment Day
- John Connor: (voiceover) The future has not been written. There is no fate but what we make for ourselves. I wish I could believe that. My name is John Connor, they tried to murder me before I was born, when I was 13 they tried again. Machines from the future. Terminators. All my life my mother told me the storm was coming, Judgment Day, the beginning of the war between man and machines. Three billion lives would vanish in an instant, and I would lead what was left of the human race to ultimate victory. It hasn't happened, no bombs fell, computers didn't take control, we stopped Judgment Day. I should feel safe, but I don't, so I live off the grid - no phone, no address, no one and nothing can find me. I've erased all connections to the past, but as hard as I try I can't erase my dreams, my nightmares.
- Terminator 3: Rise of the Machines
- John: Why is this happening again?
- Sarah: I don't know.
- John: You stopped it.
- Sarah: I guess I didn't.
- John: But you can. You changed the future, you just didn't change it enough. So you can do it again.
- Sarah: I don't know, John.
- John: I can't keep running. I can't. I'm not who they think I am. Some Messiah.
- Sarah: You don't know that.
- John: I know. I can't lead an army. Maybe that's you, but it will never be me, so you've got to stop it. Please. Mom...
- Sarah: All right.
- John: All right what?
- Sarah: I'll stop it. I'll stop it.
- The Sarah Connor Chronicles, Episode 101: Pilot
- Throughout the film, Reese (in the Extreme Edition) and John make references to a message that Reese gave to Sarah in The Terminator; they constantly repeat "The future is not set. There is no fate but what we make for ourselves." However, that second sentence never appears in the first film (The line does appear in the script, however, and was presumably shot and subsequently deleted from the first film).