Philosophers asked "After several hundreds of years of maintenance, if each individual piece of the Ship of Theseus were replaced, one after the other, was it still the same ship?" Yes we keep evolving every moment, everything our body, mind and soul experiences, changes us. We are our intentions, we are what greek philosophers called was our 'Nous', what we want to do and what defines our existence us is the actions we take to realise those intentions.