A signatue does not guarantee anything about 'you'.

A signature can be counterfeited or imitated. A signature also implies that we are coherent, sovereign individuals that exist prior to history and culture. When I write, "Bosco" that does not mean that I existed before language. In fact, it's the act of naming that gives me an identity, but I'm not the same every time I sign my name. So, a signature doesn't guarantee anything.

Each repetition of Bosco Redmond will differ although I must be able to sign Bosco Redmond in a manner that can be recognised but my handwriting is mediated by my mood.