The author of The Elegance of the Hedgehog, Muriel Barbery, is a philosophy professor. Therefore, there is a lot of musing on philosophical questions done by primarily Renee, who identifies both Husserl and Kant and their philosophies as she espouses upon them. Paloma, on the other hand, grapples with some of the same ideas, but, as an adolescent, is not as experienced with the actual philosophers who have proposed these ideas as Renee. These philosophies, however, affect the way both Renee and Paloma view life.
Edmund Husserl was the found of a philosophy called phenomenology. This is the study of human experience in which considerations of objective reality are not taken into account. He believed that peoples' experiences were the source of all knowledge, not necessarily what was defined as "real". He said that an object could not be known outside of a person's experience of that object; that the object in and of itself had no reality apart from a person's experience (I know, it's complicated!). Renee defines it as follows:
This is phenomenology: the "science of that which appears to our consciousness."
Kant, another philosopher, believed in the theory of idealism, a theory that maintains that the ultimate nature of reality is based on the mind or on peoples' ideas. In a sense, this is similar to Husserl's "experience" theory. Kant believed that using reason without applying it to experience would lead to illusion but that on the other hand, if experience were not used in conjunction with reason, it would be purely subjective, so the two must be used together.
In chapters 5 and 6 of the novel, Renee grapples with these complicated thoughts and declares:
After one month of frenetic reading I come to the conslusion, with immense relief, that phenomenology is a fraud.
She says it boils down to two questions: What do we know of the world and What is the nature of human consciousness? Then she tries to apply these two ideas to her life saying that what difference does it make if one knows the origin of an annoying itch. The knowledge of the experience does not change the fact the itch is miserable.
Then she applies the idea to Kant saying that his idealism has only resulted in the conclusion that we don't know a great deal about the world. How can one be certain that a cat is really a cat, she asks? Just because we perceive it to be a cat, does that make it a cat? And who cares if it really IS a cat or not, it still needs to be fed every day.
Renee is fascinated with these philosophies, but she is also practical and after her lengthy ruminations on each philosophy declares that they are both useless.
In her own way, Paloma tries to figure out the meaning of life, how absurd it is, what the meaning really is behind things, people, etc. She may not label the philosophical thought in the same way Renee does, but she grapples with the same problems and eventually comes to the same conslusions.
The dilemma of determinism is this: if something happens as a result of a chain of events (determined) and the cause goes back to a time when the agent is not responsible for any of the actions, then the agent is not responsible for the results. If the action is NOT the end of the chain of reactions, then either it or its cause has occurred at random, no earlier events brought it about and nobody is responsible for it having happened. Whether determinism is true or false, the responsibility for something happening is an illusion. (I know, I don’t get it either)