Why can’t Siddhartha follow the Eightfold Path?

As Siddhartha is leaving, he runs into Goatama in the woods and questions the Buddha about his teachings. Siddhartha compliments the theoretical coherence of Gotama's worldview, the ultimate unity of creation and the incessant chain of causes and effects, but remarks that Goatama's doctrine of salvation, the transcendence of causation, calls into question the consistency of his position. Goatama responds by saying that he goal of his teaching is not "to explain the world to those who are thirsty for knowledge. It's goal is quite different; its goal is salvation from suffering. That is what Goatama teaches, nothing else" (33). Siddhartha, afraid that he has offended the Buddha, reiterates his confidence in the Buddha's holiness, but expresses his doubt that any teaching can ever provide the learner with the experience of Nirvana. And while Gotama's path may be appropriate for some, Siddhartha says that he must take his own path, lest self-deception overtake him and he admit to Nirvana before having actually attained it. The Buddha admonishes Siddhartha to beware his own cleverness then wishes him well on his path.