The Myth of "Only Dreaming You're Lucid"
I'd like to take a moment to clarify why the idea of "just dreaming you're lucid" does not actually make any sense, and why this line of thinking is unhealthy.
A lot of people unfamiliar with lucid dreaming often say things such as "oh, you were only dreaming you could control your dreams; you weren't actually in control", and many new lucid dreamers ask "how do you know if you were actually lucid and not just dreaming you were?". It seems like a lot of people don't actually understand the concept of dreaming, and so they say things like this that do nothing but hold on to the idea that dreaming is somehow fake in its entirety.
Dreams culturally are frequently dismissed as fake, which is frankly not true. When we say "I dreamt I robbed a bank", what we are saying is "in a dream, I robbed a bank". By saying you dreamt something, all you're doing is giving locational information (that it happened in your head) and giving some information as to what your state of mind and the solidity of the experience was.
There are two reasons why people think dreams are fake. Firstly, what happens in dreams has no effect on the outside world. If you rob a bank in your dreams, you committed no crime in waking life. Secondly, and most importantly, the dreamer usually thinks he's awake during the dream. In a normal dream, if you rob a store, you think you're actually robbing a waking life bank, and this bank might have an analog in waking life. When he wakes up, he realizes he didn't actually rob a bank in waking life, and so he deems the experience as fake. However, this isn't true; he still robbed a bank (or at least had an experience that can be closely described as robbing a bank), it was just a dream bank.
What happens in dreams is real. For instance, the emotions felt during dreams clearly are real. If your mother died in a dream, you would probably feel really sad and maybe cry, and these emotions are not fake. If you wake up during or right after one of these dreams, oftentimes you still feel overwhelmed with emotion. The key is that your mother didn't actually die, you just had an experience of her representation dying which you thought was her, and so you experienced real sadness from it. The experience and emotion are not fake, you were just mistaken as to the situation, and no physical consequences arose from the event.
This is why it makes no sense to say you didn't actually control your dream and that you were "only dreaming". You didn't think you were awake while you thought you were "controlling your dream", so to say it didn't actually happen makes no sense. In the same vein, you can't "dream you're lucid" while not actually being lucid. You can't be lucid, defined as knowing you're dreaming, while simultaneously thinking you're awake. Everything in dreams is real; it's only your understanding of it that may be wrong or "fake".
That's not to say you can't be wrong about how lucid you are, or have different levels of lucidity. We use the term lucidity to mean both the idea that you understand you're dreaming and your clarity of thought while dreaming, and these both can vary. This is why lucidity is best mapped as a spectrum rather than being binary. What we call "low lucidity" is having the inclination or realization you're dreaming without it really sinking in, and maybe still being in an odd frame of mind. This is what some people usually mean when they say they were "only dreaming" they were lucid, but their terminology fails them.
Sorry for the long post, but I feel this is a topic that should be addressed. People just throw around the phrase "only dreaming", but it's really dangerous to apply it to everything to do with dreams. It really only applies to a certain subset of dreams: those in which you think you're doing something in waking life, and even then it should be used carefully.
