I observed that I was subject to gravity on earth. Every time I jumped I came back down. Someone made up the term "gravity" and I said "oh thats what that is called". Note I was able to observe it. I never saw my or anyone else's right to life. I saw people die that obviously did not want to die.
What makes you think its important to me to say that unalienable rights do not exist? For that matter why is it import to you that they do exist? Were the founders and philosophers humans or gods? I was always under the assumption they were humans prone to corruption and all other negative things the rest of us were prone to.
And are you not able to observe that people think? That they speak? That they care? That they hope? That they enjoy activties without or without others? That they enjoy owning certain things they consider their own property to use or abuse as they wish? That to be able to go where you please and do what you want that does not interfere with others is a precious thing to have? To be who and what you are, and nobody telling you can't be that? To profess what you do and do not believe with no fear that you will be punished or hurt or killed for that?
The Founders were by no means the first to recognize and embrace a concept of such things being the natural state--the natural right--of humankind. They didn't make it up. That they embraced the concept and adopted it into their own value system and incorporated it into the Constitution under their own label of "God given" rights should not negate the principle in any way. They could have called it the Mickey Mouse phenomenon and it would still be what it is.
Yes I can observe people do those things. I call them abilities. A very dominant ability we as humans have is the ability to create concepts out of thin air and in contradiction to reality. It makes us feel safe that some all powerful entity gave us rights so we make it so. Your words painted a beautiful and stirring picture complete with harps and accompanied by a chorus. However that is just my imagination. There are no harps and no chorus. Same thing with rights. If you have the right to life why do people die that don't want to?
Yet you DEMAND that no one has a natural right to USE THEIR ABILITIES unless they are first GRANTED THE RIGHT TO DO SO. Your argument is RIDICULOUS.