>>6753236>those never last more than a century or a milleniaJulius Caesar has been there for 2 millenia and still kicking. Also, unless they're somehow proved wrong (and maybe not even then), people like Newton and Einstein will be known and their theories studied for as long as we are here.
>What will they be worth when all humanity ceases to exist or all the people who care about your legend die?Nothing, after all, nothing is eternal. Nevertheless that's the maximum you can get.