Two main concepts presented in this dissertation are the principle of hospitality and the problem of European cosmopolitanism. Thinking, learning and critical questioning of these concepts allow to clearly comprehend some of the most important ethical and political problems of our time, particularly migrant crisis or the politics of exclusion, actual in many European national states. In the heart of these problems is the (un)acceptance of the ones we consider strangers, others, aliens, foreigners, in other words, the ones who do not belong to our community or to the body of the nation. The term hospitality is initially interconnected with the term hostility and there is constant wager between them. We observe this interconnection from the mere beginning, as the terms hostility and hospitality share the same Latin root – word hostis. Originally, the notion of hostis involved someone in an equal, reciprocal relationship demanding trust, a concept of laying down of one’s weapons – a conversion of hostility into hospitality. Later, when interpersonal relations of trust were replaced by abstract relations between impersonal political communities was when hostis assumed the connotation of enemy. Because hospitality was intrinsically linked to the possibility of hostility, it became the drama of choice and decision. The wager, or drama of hospitality, is most obvious when we are faced with a stranger – do we open or close the door? Do we reach for a weapon or extend an open hand? Do we open European doors to immigrants from old colonies when we need labour force and close it when we do not know how to integrate thousands of Syrian or Afghan refugees? More important, what do we do with the ones who almost succeeded on their way to Europe and reached its front door. These people, locked in detention centres and treated like the worst criminals must be a part of our cosmopolitan agenda. As a cure for millions of migrants who lost their homes and citizenship (or did not acquire it at all), the right of asylum, defined at the Geneva Convention, was granted to every human being. The Western principle of hospitality marked the essence of the global asylum system. Even though such principle can be traced from prehomeric tradition, European modern understanding of hospitality was strongly marked by the evolution of the principle itself, which began at the end of the Middle Ages. From that point, hospitality, previously considered as an act of Christian charity, is transformed to the universal human right. The period from the second scholastic and the writing of Francisco de Vitoria at the beginning of the 16th century to Immanuel Kant’s essay Toward Perpetual Peace in the late 18th century was crucial for this evolution. Enlightenment scholars, who embraced the idea of universal humanity, were influenced by their ancient colleagues, Roman Jurists and Stoics above all others. In the heart of the Stoic understanding was the desire to replace the centre role of the particular Greek polis with the idea of cosmos where humanity could live in harmony. Thus, the human simultaneously inhabits two worlds – one local where one is born; and the one vastly broader that is common to us all and allows equal values for every person. Ancient ideas were most clearly portrayed in Immanuel Kant’s cosmopolitan federalism and moral universalism, which have arisen not only from the past, but also from the work of his contemporaries. Kant’s cosmopolitanism is impossible without the principle of hospitality, which is the right of every man on the surface of the Earth for protection and sanctuary in every part of the world. It determines the right of the visiting foreigner not to be treated as an enemy. Without such universal comprehension of hospitality, the realisation of the law of the world citizenship (cosmopolitan law) becomes impossible. By Kant’s interpretation, the hospitality ceases to be the act of philanthropy and becomes legal requirement obtainable for every human being in need. But, in the same period when Kant formulated his most important essays on cosmopolitanism, the idea of the sovereign national state started to rise. The 19th century legal and political theory introduced notion of European political and economic supremacy above those American, African or Asian. The East and the South became a playground for the Western imperial pretensions, which is why understanding of hospitality and cosmopolitanism vanished, not just from political practice of the time, but also from the work of mainstream European scholars. They were focused on the new, promising concept of the nation, even though concentration on the nation facilitated dissolution of European empires and clashes of the continental powers. These clashes resulted with the two World wars with millions of dead, injured or displaced. That is why, in the second half of the 20th century, some of the European scholars turn to the renewal of the concepts of hospitality and cosmopolitanism. What they had in mind was the fact that, despite moral allegiance to humanity, people lived in states, which logic is reduced to the internal and external sovereignty. Therefore, what is put upon the idea of cosmopolitan community as principle problem is how to regulate relations between people when states stand in between. Although foreign philosophy and political literature contained numerous academic texts on this topic, strong aporia connected with the term hospitality, from its beginnings, did not allow simplified conclusions, nor unified application of this principle in the interaction between individuals and states. Therefore, it has become the very source of theoretical and political disputes and repeated inquires, as well as the reason for writing this dissertation. Liberal theory has been occupied for decades with the idea of distributive justice. Such justice has been unable to find adequate solutions for problems outside national borders – even though the basic idea of moral cosmopolitanism equals moral value of each human being; from which the universal moral responsibility towards every human is deducted. The cosmopolitan ideal demands that some fundamental principles of justice govern relations between people everywhere in the world. However, discrepancies arise from inexistent consensus on the levels of responsibilities for others and on whether those who do not share the common ethnical, cultural, religious and political identity are those to whom the same responsibilities apply. Even if we could reach a consensus, it would be unsustainable in practice. That is the reason why focus of the dissertation was placed not only on the work of authors who embrace the idea of brotherhood of all people, but also on the authors who reject the possibility of application for the idea of strong moral cosmopolitanism. As said above, after Kant, theoretical directionality (as well as political practice) was focused on the idea of nation and on legal positivism; so only after the WWII, the interest of philosophers and political theorists became again focused on the question of acceptance of the Other. Amongst many, the contributions of French philosophers Emmanuel Levinas, Paul Ricœur and Jacques Derrida stand out. Derrida's contributions had the broadest influence so they are specially examined in the dissertation. Namely, Derrida constructed the notion of absolute as opposed to conditional hospitality, which he attributes to Kant. The main objection on Kant's notion is that legal definition of hospitality is inevitably perverted every time the person seeking hospitality is posed with conditions. Derrida distinguishes the politics of hospitality from the ethics of hospitality. Politics are marked by obstruction, borders and caution, while ethics of hospitality demands radical opening toward the Other and his acceptance, disregarding all risks which may arise. The basic idea here is that pure hospitality is unconditional; if you truly welcome a stranger, you do not ask where he or she came from or for what purpose. You do not ask a stranger for ID or passport because this hospitality is not about a contract or an exchange – it is about radical exposure to the Other. That is the level of risk that real hospitality involves. Derrida himself acknowledges that such hospitality is impossible – but he suggests we should strive for it anyway. Such radical understanding has attributed criticism by post-modern authors who have deemed it inapplicable ethical ideal. Diacritical hermeneutics, represented by the work of philosophers Paul Ricœur and Richard Kearney, does not criticise Derrida for the sake of plain criticism, but builds on Derrida’s foundations offering the concept of linguistic hospitality as the possible solution for any other kind of hospitality – interreligious, intercultural or international. As Kearney explains, Derrida is well aware that world belongs to everyone, but within the borders of national states it belongs to some more than to others and that is why some form of immigration/emigration laws are inevitable. On the other hand, hermeneutic approach calls for more caution and opens the possibility for saying no to some strangers migrants. Not all strangers are in need of protection and sanctuary. Hermeneutics, thus, addresses the need for critical informed ethico-political judgement that will discern between good and evil and embrace conditional rather than unconditional hospitality.