Nature is a dual force in the novel. It brings great joy but also great pain. Characters often get angry about other forces beyond their control (the tannery, their children). However, for all the grief they get from nature, they never come to resent this powerful force. One of the greatest philosophical points of the book is that nature reflects the arbitrary beauty and suffering inherent in life. One can only appreciate what there is to appreciate, and endure what must be endured. Though nature often hurts her, in the end it is the thing for which she endures, knowing that it too endures and will last long after her.
Nature is a cruel force, but it stands in contrast to the even more cruel force of urban modernity, which destroys the environment and the traditions of India. Within this paradigm, for all its challenges, nature is definitely the lesser of two evils.