existential philosophy existential question existential questions existential risk existential threat existential threats existentialism existentialist existentialists existenz existing existing access existing account existing accounts existing actions existing active existing activities existing administrative existing agreement existing agreements existing aid existing air existing aircraft existing airport existing alarm existing and emerging existing and future existing and new existing and new customers existing and planned existing and potential existing and potential customers existing and proposed existing and prospective existing app existing application existing applications existing approaches existing apps existing architecture existing arrangements existing article existing assets existing bank existing barriers existing base existing basic existing beds existing body existing booking existing bookings existing brand existing bridge existing budget existing building existing buildings existing business existing business model existing businesses existing cable existing canadian existing capabilities existing capacity existing capital existing car existing case existing cases existing cash existing categories existing cell existing centres existing challenges existing channel existing channels existing chemical existing chemicals existing church existing class existing classes existing classification existing client existing clients existing code existing collection existing commitments existing common existing communication existing communities existing community existing companies existing company existing competitors existing components existing computer existing concepts existing concrete existing condition existing conditions existing connection