Existential semiotics is simply combination of the classical semiotics - Saussure, Peirce, Lévi-Strauss, Greimas - and the continental philosophy - in the line of Kant, Hegel, Kierkegaard, Jaspers, Husserl, Heidegger, Arendt, Sartre, de Beauvoir. It has launched new concepts to the semiotic study of our time, such as presign, actsign, postsign, quasisign, transsign, endosign, exosign, phenosign,genosign. From the Paris School it adopts notions like isotopy, semanalysis, modalities. Original issues hitherto not often appearing in the standard semiotic vocabulary are such terms as Dasein, transcendence (trans-ascendence and trans-descendence) and the zemic model (cf. Taratsi 2000, Tarasti 2015, Tarasti ed 2023). It is aiming for a theory which can be applied to diverse cultural phenomena taking into account the 'semiotic self' both in the individual subjectivity and as a collective epistemic category. Thus one may already speak of 'existential human sciences' which does not mean any return back to existentialism. This paper is supposed to be a general introduction for the whole panel "How Do We Exist With Our Signs... On the Epistemological Foundations of Semiotics" preparing a background for future discussions and at the same it gives the most important points of departure for all papers - both: theoretical and analytical ones.