Selflessness

I am reading about how people and objects exist. One of the concepts of this is that people do not inherently exist. I am new to this idea, so for me to understand it I have to start small.
There is no such thing as beauty or ugliness, nothing is either lovely or ugly they only become so when compared to other things.
The second part of this is that objects only exist because of someones perception of them. For example someone sees a shape in the darkness that they think is a cat, the shadow is not a cat it is just perceived that way. I think this is supposed to lead us to think about our own sense of inherent existence. Just like the shadow was not a cat, we are not us. This means that we are not independent, we exist because of many factors and conditions. I am not sure I am on the right track about this, I will have to meditate on it. I do understand the idea of dependent arising though.
That is the idea that nothing just happens, the plant or the flower depend on many factors for their existence.