La théorie des nullités, telle qu'exercée aujourd'hui en Droit civil, souffre d'une grave incohérence tant dans sa conceptualisation que dans son application. Il serait adéquat de parler de "cumul de théories". Car, de toutes les théories qui ont été élaborées, nulle n'a réussi à s'imposer comme seule compétente à régir toute la matière, et aucune, en revanche, n'a été définitivement éradiquée de la pratique juridique. De l'inexistence, à la rescision, aux nullités relative, absolue, virtuelle, partielle, conventionnelle, unilatérale, les modules du système d'annulation s'entassent sans qu'ils constituent un ensemble homogène susceptible de former une théorie pertinente, digne de la réputation historique et mondiale du Code civil français. Dans le mouvement d'européanisation et de mondialisation de l'activité juridique et législative, d'une part, et à l'heure où le chantier de la réforme du droit des obligations et des contrats est lancé, d'autre part, il semble que seule une théorie de nullité débarrassée de toute classification astreignante et dogmatique saurait remédier aux difficultés que soulève l'inlassable variation des circonstances. Dans cette perspective, désencombrer la nullité nous amène à dépoussiérer le noyau de la théorie et à remettre en avant le principe du but de la loi. Ceci implique aussi un élargissement de l'imperium du magistrat pour faire valoir le but de la loi, soit pour assurer la sauvegarde de l'intérêt général ou de l'ordre public, soit pour renforcer la protection du contractant faible au contrat. / The theory of nullities, as exercised nowadays in civil Law, suffers from a severe incoherence as much in its conceptualization as in its applicafion. It would be adequate to talk of “accumulation of theories”. Since, of all the theories that have been elaborated, none has succeeded to impose itself as the only competent to cover the entire subject, and none, on the other side, has been definitely eradicated from the juridical practice. From the inexistence, to the rescission, to the relative, absolute, virtual, partial, conventional, unilateral nullities, the modules of the system of nullification accumulate without forming a homogenous set liable of forming an apt theory worth the historical and global reputation of the French civil Code. In light of the movement of Europeanization and globalization of the juridical and legislative activity from one part, and at the time when the site of the reform of the of the law of obligations and contracts has been launched, from the other part, it seems that only a theory of nullity free of any demanding and dogmatic classification would be able to remedy the difficulties arising from the tireless variation of circumstances. In this perspective, emancipating the nullity will lead us to dust the nucleus of the theory and put on forth the principle of the goal of the law. This also implies enlarging the “imperium” of the magistrate to emphasize the goal of the law, either to ensure the protection of the general interest or public order or to reinforce the protection of the contractor weak towards the contract.

This thesis discusses the limits of statute of contractual obligations solely from the perspective of conflict of law rules. It is based primarily on the analysis of national conflict of law rules contained in Act No. 91/2012 Coll., On Private International Law. There are also analyzed relevant standards of the European Parliament and Council Regulation (EC) No. 593/2008 on the law applicable to contractual obligations (Rome I) and conflict of law rules in the German Initial Act to the Civil Code, as well as in the Swiss Act on Private International Law. The primary hypothesis of this work is the concept of a single contractual statute, which governes contractual relationship since the early beginning to the end. The secondary hypothesis follows the departure of German international private law from the principle of seat for the principle of incorporation. Another hypothesis explores the safeguarding of property rights once acquired, if the substantive legal facts are in the mode of the original substantive statute closed that no means no and yes means yes, but ... This work also examines the question of whether the European legislator through the unification of rules of conflict of law removed the deficiencies that resulted from the application of autonomous national conflict of law rules or...