Are the chaos and complexity theories the same? While there are similarities in that these theories are trying to explain the way our world works and how we can solve the existing problems, they are different. This might come as a surprise to you, but Chaos Theory is a study of deterministic systems while Complexity Theory is non-deterministic. While there is a way to find out what effect the change of a variable will have on a system using Chaos Theory, it's impossible to do the same for the system of Complexity Theory.
To make it clearer, we can say that there is always a way to know the outcome in a Chaos Theory system. According to the famous Butterfly Effect, if there is a minor change in a system, its effect will be seen within a long enough period of time. If your alarm clock breaks and does not wake you up on time, you get late for work and have a fight with your manager. It leads to a bigger conflict and, as the result, you get fired. If your alarms clock chooses not to break up (let's suppose it can control that), then you will be working at this place for a long time. These are two systems with one different variable but we still can determine the outcome.
The non-deterministic nature of the Complexity Theory means that there is no way of knowing what the final result will be because it is too difficult to compute it (not only for humans but for machines as well). In this way, Chaos theory can't be considered to be a part of the Complexity Theory.