It seems to me that choosing a purpose, while it could be the answer for some, may be seen as an artificial purpose by others. I think it would depend on how you come to the conclusion, "Okay, this is it - this is what I am here for - the reason I exist," if say, you're leafing through a magazine that lists the best life purposes that you can choose as your own.

Bringing destiny into the picture though, could serve to validate a chosen purpose I guess, if we're somehow able to logically link the two together in our minds.

It seems we'd have to spend a considerable amount of time convincing ourselves that our choice really, truly is our special purpose though, which is entirely possible to do, but like I suggested, to me it would still feel artificial.

Thank you for the great comment and for the tip!