Appearances are one of the main concerns in eighteenth-century novels, but most studies relegate them to a subordinate role, in relation to other issues. Following Slavoj Žižek's understanding of ideology, Alain Badiou's concept of logics of appearances and Jacques Derrida's deconstruction, this thesis offers a sustained analysis of a series of issues of appearances in the eighteenth-century novel, through an exploration of sixteen defining traits, based on Samuel Johnson's definitions of ‘appearance', ‘appear' and ‘apparition'. The concept of appearances allows for an interrogation of ideas, beliefs and positions about most things, including appearances themselves, as they remain open, in their structure and logic, destabilising and deconstructing the ways of thinking that try to contain them. This thesis argues that eighteenth-century novels reproduce, resist and deconstruct the eighteenth-century ideology based on a desire to neutralise the effects of appearances. Through a wide range of eighteenth-century novels, from Robinson Crusoe to Evelina, it argues that novels destabilise the relationship between appearance and being, proposing the multiple appearances of beings and becomings. William Godwin's Caleb Williams is taken as a paradigm, shown to contain most of the issues of appearances in the eighteenth-century novel, revealing that whatever there is, it must be supplemented by appearances in order to appear as reality. This thesis argues that novels came to grasp such a truth of appearances from the beginning of eighteenth-century, by locating appearances subjectively, making more evident the multiplicity and extent of fictions, allowing readers an increased degree of awareness of the fictionality of reality. Thus, this thesis makes a significant contribution to the study of issues of appearance and ideology within literature studies by establishing the genre of the novel as the event of appearances in the eighteenth century.