A Passage to India examines these things by portraying the East and the West differently. The West is seen as the educated, civil society. The East is portrayed as a romantic, unchanging other. Forester does this to emphasize how the societies are viewed differently.
One lens to view this book with is Edward Said's Orientalism. It says that the West views the East in an unchanging way, and it views the Orient as having one culture (even though it is made up of thousands). My favorite example is the microwave dinner brand "Asian Sensations". The food is all called Asian despite being cuisine from Thailand, China, and Japan.
One way to answer this question is to figure out who Forester gives identity to.
In A Passage to India, life in Chandrapore, and indeed throughout the British Empire, is deeply fissured along racial lines, with the white Europeans on one side, and everyone else on the other. Indians are referred to as "Orientals," an out-dated racial term that was applied to everyone living east of Europe, from Turkey all the way out to China. Orientals were stereotypically considered to be exotic, sensual, passive, and backward, as opposed to the intellectual, civilized, progressive Westerner (source). Thus Orientals, such as the Indians in A Passage to India, were considered unable to rule themselves, essentially needing the British Empire to help them toward civilization (despite the fact that they had civilizations of their own). Even as the novel criticizes this stereotyping of Orientals – or "Orientalism" – it is itself not entirely free of the Orientalist attitude. The narrator makes broad generalizations about Orientals, about their psychology and their sexuality, that shows how entrenched the Orientalist attitude is even in a novel that is sympathetic to them.