As stated above, it is a nelief based thing not fact. Not sure about others, but in my experiences there not all good or bad. Life in general is not black and white. Like people, energetic or spiritual beings have the capability to be both, with their own unique personalities
Toxic Dragon I assume that you have not really worked with many spirits. Demons are essentially beings of a very chaotic nature. There are some in which are indeed hostile and can be dangerous. It is also the same with Angels.
All spirits are residual energy. They cannot effect you physically. In a technical sense they are thought forms created over time by people's fears. The mind is a very powerful organ it can convince you that things are there when they really are not. The 'pain' one may feel is psychological.
There are different beliefs as to what they are and no scentific eveidence of them to acutally to be real.
Granted this is magic as I have once heard science is what can be explained whereas magic is what has yet to be explained, however both go hand-to-hand with one another.
Demon is a label, the gods of one generation become the demons of the next. People create demons in the form of thoughtforms and the continued belief and fear allows them individuality and greater roam as time goes on. It is a case of psychological projection via magical means.
When it comes to spirits, I always think that listening to what someone else thinks of a spirit is like listening to rumors on a playground filled with adults too scared and pathetic to be a real occultist and experiment.
If you have any fear when it comes to working magic, you are going to do a poor job in my opinion.
Like has been mentioned above, demons exist in many forms and are not always evil. They are however somewhat unpredictable and chaotic.
From my own experiences, demons exist and are very real, but can only really cause you the most harm if you believe of their existence.
That being said, most of us can agree that there are various forces and "spirits" in the universe that help govern our thought processes, and therefore they are at least partially a figment of the mind.
I can't say they do or do not exist. I personally don't even know what to think. I do agree a bit that they could be a product of thoughts,but also they could exist,just not how we think they do. Man...now this will be on my mind all day.