Realism is the prevailing mode of the play, with its focus on an ordinary family in an ordinary domestic setting. The action and dialogue of the characters is quite naturalistic and the play's themes are on a recognizably quotidian level, dealing with family relationships and social issues, the kind of things that affect many people in real life. Its lack of real closure, its refusal to provide a neat resolution in the manner of more traditional and conventional literature, can also be deemed realistic. Its inconclusiveness mimics real life, where so often things are not worked out, settled, and rounded off.
The play is also realistic in a more specialized sense, in relation to its particular literary historical context. It first appeared in the early 1880s, and immediately courted controversy in its depiction of such sordid facts as venereal disease. In its exploration of the grim truths that might lie behind a veneer of social respectability and problematic family relationships, it dealt unapologetically with the more sordid side of human life, which conventional and polite literature shied away from. It was a harbinger of things to come, as more and more writers began to take up the challenge of depicting the darker side of human existence.
The play also employs several instances of symbolism. The symbolism is not obtrusive - it does not disrupt the dominant mode of realism - but it is important. The central symbol is that of Oswald's illness, which is congenital syphilis, unwittingly and most irresponsibly passed on to him by his philandering father. This disease symbolizes the insidious influences of family heritage, just as the play's title refers to the lingering and pernicious influences of the past as a whole - past actions, customs, and ideas. The past continues to haunt and undermine the present. The father's legacy looms ominously over the son, while his wife has been constrained by old ideas about social respectability to maintain a facade of family honour and pride.
The corruption of Oswald by his father, then, is both literal and metaphorical. Not only has he inherited a physical illness, he also takes after his father in his behaviour, most notably perhaps in his dalliance with the family maid, Regina, which is the direct echo of his father's flirtation with a servant many years earlier (Regina is in fact the product of this affair).
Another example of symbolism in the play is the orphanage which Mrs Alving erects in her husband's memory. With its connotations of children who lack parental support, the orphanage takes on an ironic significance: Mr Alving did nothing worthwhile for his son.
What about Ritualism? Is there anything in the play denotes the presence of Ritualism?