We propose to call Holosign the Firstness of Thirdness in the First Correlate. It is a Thirdness doubly degenerated, the character of generality intrinsic to the Legisign, independently of being interpreted as such. The Holosign is, therefore, the sign considered as general Form, pure mentality tending towards the future, or expectation, that every mental sign must possess in order to function as such.