Porfiry's theories in Crime and Punishment Raskolnikov commits a murder. He has a theory. Porfiry is an investigator. He has a theory too. Porfiry's is ever closer to victory. Porfiry Petrovich believes many things about the criminal nature and therefore believes that these things will happen to Raskolnikov, the man he pointed out as the perpetrator of the murder. He uses the comparison of a butterfly approaching a candle, that if he lets the criminal wallow in a mixture of freedom and terror he will be able to complete a mathematical proof of the crime, and that the criminal's best move is to say to the truth, during which effort he will ultimately lie and miss his plan. Perhaps Porfiry Petrovich is an excellent wax maker. It also has some very powerful and durable matches. He uses these skills to light and let burn a candle which causes Raskolnikov to come to him, twice so far, under the naive claim of seeing his father's watch. We know that Raskolnikov no longer has any concern for the things of the material world. He deposits everything he stole under a rock. He gave Katerina's family 25 rubles. Money and possessions are not a concern for Raskolnikov. He is there because of the undeniable strength of the light that Porfiry incessantly radiates upon him. Raskolnikov skillfully adapts this aspect of Porfiry's theory. Unlike Porfiry did with Raskolnikov's theory, Raskolnikov fails to find holes to fill in Porfiry's. Descartes believed that mathematics was the only thing that truly existed with certainty other than his own existence, his own mind. Porfiry firmly believes in the usefulness of having "mathematical" proof to determine the guilt of a suspect. Like Descartes, Porphyri is able to doubt everything, such as circumstantial evidence and inclination, to await the completion and realization of a "mathematical formula" that leads directly to the true perpetrator of the crime. However, Porfiry's equation is not yet balanced. This is why Raskolnikov is still spared for a while. Nikolay's eventual arrival interrupts this drive to develop a concrete mathematical theory for Porfiry.