Giving names to abstractions

I see something and i call it pencil. At some other time a exactly same looking thing is shown and i say that this is same pencil. Then i am shown a red pencil. I say this is different. It was actually the same pencil that was dipped in red color. Now what i see as same or not is my best guess. It is not even important whether i am right all the time, it is OK if i am able to solve for what matters to me. So, we see properties of things that are relevant to us and based on that we identify and then name it, name that abstraction of actual thing.

Now, i see a moth and a butterfly - they don't look same to me. But i say it is same as i see one has come from other. I see a candle and then wax that is melted from same candle - lot of visible properties are different but i still say it is same. Why then when i look at leaf, i am not able to see sunlight, earth, air etc. that are in it - it has come from a mixture of all of these. I consider myself to be same from birth to death even when each cell would have changes atleast once. When things evolve from each other there are times we know it is same and there are times when we don't realize it.

All the pages of a book are connected. But the books are not connected. What does this connectedness mean - a lighter connectedness when we find at conceptual level a similarity. Second, stronger connectedness when we say if we do something to one, others will be affected - if burn a page of book, the whole book will burn. Think of people on the same ship in the ocean - if ship sinks everyone sinks - everything is one. If i am a human, am i connected to other humans. No, because i can clearly see that there are boundaries - i can see myself ending and other beginning. But it is also true that that air that passes through me is the same that passes through other - so there is some thing that is shared - boundary is not very clear. Second, i can do something to one without affecting other - because both entities are self-sustaining. Independence means lighter connectedness?

What i am but a mass of cells that i can afford to move together at my will. And so is another human. On a beach it is two heaps of sand - thinking themselves as different. And i as observer see is one - just sand.