necessary truths

i really dont understand the empiricist and rationalist views on necessary truths, help?

Something can only be necessarily true if it’s self referencing. Like “There exists some entity A such that some entity A exists”. Doesn’t really tell us much. I suppose a rationalist would say that a necessary truth might lie in some identity theory. An empiricist might say that when we experience something, it is necessarily the case that we did not experience the opposite of it. Like if I see xmas lights, then it necessarily follows that I don’t not see xmas lights. Who knows man. Who knows?

empiricists say seeing is believing, rationalists think you can imagine your way to truth categorically