When I saw the original Star Wars saga as a kid, the concept of the Dark Side imprinted in me was quite simple. You did a bad thing, so you're a bad person so you go to the Dark Side and keep doing bad things.

Now, obviously this doesn't hold true in reality. In my mind it is perfectly reasonable for Luke to kill the Emperor and Vader and then just flee the Death Star and rejoin the Alliance. After all they are at war, those are enemy officers that have captured him and are taunting him by threatening with death of all loved ones and the whole operation was intended to kill the Emperor anyway.

The same would hold true for Anakin. He could have killed Mace Windu to save the Chancellor and Padme but that doesn't mean he's going to then go mad and kill all Jedis including children. It doesn't add up from a merely psychological point of view. He had a set of objectives and that made him want to keep the Chancellor alive (quite valid by the way, Mace Windu is quite clumsy on that) but just after killing him he goes into "Yes master I'll do whatever you say" which from a normal point of view will NEVER ever make sense.

In both cases it seems like the assumption is once you use the Dark Side you completely turn to the Dark Side and become a different person that you were before. That would be coherent with Anakin "dying" and Vader being born.

Is that the way the Dark Side works? Is there any canon information about what happens when someone turns to the Dark Side? Specifically to whether they become a different person or how he or she actually changes?

Note: Vader is angry after he finds out Padme is dead, even though he's already turned.

Example of what I mean. In Buffy they explain how people that turn into Vampires lose their soul and it's taken over by a demon, and thus they are, in all effects, a different person with their memories.

  • 3
    Anakin's "turn" wasn't quite as abrupt as you've described there. He had clear allegiance before that, and had executed the Emperor's will multiple times. The main one being the execution of Dooku, which was completely against the Jedi code. Based on this I would say there must be some kind of chemical reaction with the midichlorians within the host and feelings of anger, hate and jealousy (and fear). Coupling that with his abhorrent actions in the execution of Dooku and the Sandmen, I'd say his turn was rather inevitable much to the futile attempts of Obi-wan to bring him back to the light.
    – John Bell
    Sep 1, 2015 at 12:43
  • 2
    You also have to take in to account the fact that he seemed to immediately realize what he had done. He knew the only one who would support him now (mistakenly) aside from Padme would be the Chancellor. Anakin never demonstrated particularly strong moral fiber throughout the series so this was the straw that broke the camels back.
    – kylieCatt
    Sep 1, 2015 at 15:20
  • 3
    I must disagree with @JohnBell. Yes, there are some signs of some internal transformation of Anakin's character, as well as a blatant disregard of the Jedi code... but still his transformation to the Dark Side is quite abrupt and, in my opinion, clumsily handled. It doesn't help that Old Republic Jedi are idiots and Mace Windu himself is insufferable -- I cannot help but side with soon-to-be Darth Vader in the scene of Mace Windu's execution. Mace Windu is an ass, he explains himself poorly, and wants to execute a disarmed opponent while disregarding Anakin's reasonable objections.
    – Andres F.
    Sep 2, 2015 at 15:03
  • 4
    Also, the execution of young Jedi pupils (I refuse to call them "younglings") by Vader doesn't follow at all from Anakin's fall to the Dark Side. It seems Anakin goes from "slightly confused about his loyalties" to "full-blown child murderer" in about 5 seconds. It would make a lot more sense, from a "slightly confused" Anakin perspective, to attempt to convert young Jedi pupils to the Dark Side. In short, I blame it on extremely poor writing.
    – Andres F.
    Sep 2, 2015 at 15:05

4 Answers 4


The Dark Side does affect you both mentally and physically, in many ways it is like an addictive drug in that the more you use it, the more you change be become dependent on it:

The dark side, much like a strong, addictive narcotic, affected not only the mind of the user but the appearance as well. As one immersed oneself deeper within the dark side of the Force, its malevolent power took a toll on the body. Darth Bane explained that the reason for this physical degradation was because flesh and bone lacked the endurance to channel the immense power of the dark side indefinitely. Revan also explained that while the light side and Jedi teachings were devoted to preventing physical change through the Force, the dark side changes had to be accepted by the Sith, or they would fail due to their attempts at moderation.

As for completely hollowing you out and replacing you with a demon of some kind, that doesn't happen. Although after enough time had passed and you fall far enough to the Dark Side, it would probably appear as if the old you was indeed dead and replaced by some evil entity.

One interesting case is Darth Nihilus, who was totally consumed by the Dark Side and became some sort of Dark Side poltergeist. Something like this is extremely rare and as far as we know, only ever happened to Nihilus:

In time, the corruption could go beyond mere cosmetic details and directly impair physical abilities. King Ommin of Onderon was a proficient Sith sorcerer for most of his life, and the dark side held him under its decaying influence until he eventually became incapable of movement and needed support from a cyborg exoskeleton in order to survive. Another extreme case of dark side corruption was Darth Zash, whose extensive study of the dark side led to immense physical degradation and eventually a fatal terminal condition. The worst case of this transformation would be Darth Nihilus, who was completely consumed by the dark side both mentally and physically. Eventually, he became an aberration of the dark side that existed only to consume life.

enter image description here

  • 1
    Interesting, however I'm not sure that explains the events that unfolds on the movies. The changes in Anakin are quite radical, at the start of the movie he's best pals with Obiwan and talking about the "Jedi Way" and by the end of the movie he's killing innocents and trying to kill Obi-Wan. These are supposed to be effect of turning, not of he becoming mad... In return of the Jedi is also assume by the Emperor that killing Vader and embracing the "Dark Side" will make Luke betray all his friends and family... Sep 1, 2015 at 14:56
  • 2
    @JorgeCórdoba remember he kills those sand people that killed his mother? Women and children included. He was always prone to extreme acts of violence. Plus he wanted enough power to protect/revive Padme, so he was willing to do whatever it took, which happened to involve killing a bunch of Jedi kids.
    – Ingu Shama
    Sep 1, 2015 at 15:01
  • 3
    yes I admit that can be used as a valid explanation albeit being disappointing. That will mean that the Dark Side didn't turn Anakin but that he's been sort of a psychopath all along, just waiting to explode, which is fine by me but then the movies didn't really make a good work portraing that (of course movies where targeted to a young audience anyhow). Sep 1, 2015 at 15:05
  • 4
    Ingu Shama - No, butchering the Sand Children was not a sign of what he would eventually become, it was a sign of what he already was. I say that Anakin was already evil at least as early as when he killed Sand Children, despite still belonging to the Jedi and following the Light Side of the Force. I say that he became evil years before he switched his allegiance to the dark Side. Sep 2, 2015 at 1:47
  • 1
    @DVK I didn't know that... I'll have to update the references
    – Ingu Shama
    Sep 2, 2015 at 6:19

I've thought of that myself.

The implication that was made in The Empire Strikes Back and in Revenge of the Sith is that use of the Dark Side affects one's mental state, and at least in part this is because of how it's invoked.

From a Jedi's perspective, Yoda says: "Once you start down the Dark Path, forever will it dominate your destiny. Consume you, it will."

And, "A Jedi uses the Force for defense, never for attack."

Fairly vague, but in Revenge of the Sith, Anakin says, quoting knowledge gained from his Jedi teachings:

"The Sith rely on their passion, they think inwardly, only of themselves.."

Later, Sidious says to Vader: "Do what must be done Lord Vader. Do not hesitate, spare no one. Only then will you be strong enough in the Dark Side to save Padme."

Now it's possible that Sidious was just lying in order to convince Anakin to do what he wanted, but if we take this statement at face value, it says something.

First, the Dark Side responds to aggression: "I can sense your anger, it gives you focus, makes you stronger" or from Dooku "You have hate, you have anger, but you don't use them."

Second, allowing compassion to influence one's decisions weakens one's connection with the Dark Side.

The Dark Side therefore seems like something that will tempt someone to go further and further, like trying to stop eating chocolate cake after having a bite. It leaves open the possibility that one could try to be disciplined and use the Dark Side "responsibly", but that it would be exceedingly difficult.

As you point out, this makes for a rather simplistic view of aggression and morality. Why can't one channel anger, and still make moral decisions? Then again, the Jedi are very controlling of their members.

Perpetuating this way of thinking seems like a way that the Jedi kept people in line with their world view, rightly or wrongly: "You've gotta act our way, and think our way, or you'll turn evil. Oh, and you're not allowed to have a lover either."


Anakin's strength in the force always makes him arrogant (as we see in Attack of the Clones + and even the Phantom Menance) but it's fear that turns him to the dark side. In Episode II and the first part of III he fears losing Obi-Wan as much as Padme, but by the end of Revenge of the Sith his fear of losing Padme leads him to the Darkside.

The murder of the younglings is the event where Vader really is born (more so than Windu's murder which is an instinctive action). I'd argue that their murder is part of a narcism that's an ever present in Anakin's make up. The dark side seems to weaken empathy for anyone else. A bit like using a narcotic, Anakin quickly only cares about his own needs, hence their murder.

Anakin/Vader's temper is exacerbated by Dark Side use. I think he struggles to control his temper more than any other dark side user in all the films (Kylo Ren's temper is mere tantrum when compared to Vader's) In Vader's early stages he can't control his anger. The strangulation of Padme shows how quickly Dark Side use means that the user only focuses on himself.

Obi-Wan does not attempt to reason with Vader at all in their Death Star encounter (I know that Lucas didn't intend Vader to be Anakin at this point but it luckily fits!) as he knows that prolonged Dark Side use has eradicated compassion and empathy (in the way prolonged drug use does the same - all that matters is the next fix).

Vader's treatment of Dr Alpha again demonstrates the lack of compassion, and worse the pleasure of malice with torture. Throughout the films Vader enjoys the fear he generates and views everyone as instruments in him getting what he wants. Palpatine has a similar view, a self-centredness and narcissism that is the net result of hungering for power, just for it's own sake. Many dictators display similar behaviour tendencies.

Vader lacks his master's control. Probably because he's emotionally damaged from his various childhood traumas. Vader struggles to control his anger/hatred in the first fight with Luke in Empire. He does not intend to chop off his son's hand, but such is the power of the dark side he can't control himself. One could argue that it is again fear of losing another possession (i.e. his son) rather than the oft quoted compassion that sees him tackle Palpatine. I'd argue it is selflessness that wins out, Vader is fully aware of the terrible risk of interceding on his son's behalf for his own well-being.

I don't think any of the media really tackle this question though, Vader quitting the Dark Side and releasing his hate, although oft discussed is both physically and emotionally incredibly difficult for him. As a child of the Force he personifies both side.


Simple use of the dark side doesn't necessarily result in a turn, however. Many, many light siders find themselves in extremis and draw on the dark side, yet few of these Jedi subsequently fall.

Obi-Wan uses the dark side to gain the upper hand against Maul. Luke uses the dark side when he classically beats Vader down and cuts his hand off. Anakin uses by my count eight separate dark side powers he has control of, and three more during moments of extreme distress during the Clone Wars, but doesn't turn until he seems to make the conscious decision to yield to it for his own gain.

In Star Wars Rebels, Ezra Bridger uses some of the most extreme of dark side powers he learned from a Sith Holocron with deliberate control for weeks, yet while he was clearly beginning to trod the dark path, he ultimately doesn't fall.

Yoda may say simple use of the dark side can be equated with falling to the dark side, but there's more to it than that.

  • 1
    Do you have any sources for any of these claims you could edit in to back them up? For example, the Obi-Wan claim, I can’t remember anything about that one.
    – TheLethalCarrot
    Apr 12, 2020 at 21:29

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.