One similarity between William Blake's descriptions of a tiger in his poem "Tyger" and Yann Martel's descriptions of the tiger named Richard Parker in his novel Life of Pi concerns the fact that both are awe-inspired by the ferociousness of the tiger.
In his poem, Blake waxes lyrical about the creation of the tiger, wondering how it is that God could have created such a terrifying and ferocious beast. Yet, the speaker in the poem sees far more than just ferociousness in the tiger; the speaker sees a work of beauty and a work of art. The correlation of the tiger to art and beauty is especially seen the lines, "What immortal hand or eye, / Could frame thy fearful symmetry," shown at the end of both the first and last stanzas. The connection to art is further seen in images of the tiger's eyes burning and in using art to create the tiger's heart and set it beating.
It is also important that Blake juxtaposes the tiger's ferociousness with gentleness, asking, "Did he who made the Lamb make thee?" Since the word "lamb" is also capitalized, making a clear reference to Jesus Christ, the sacrificial Lamb of God, we see that Blake is also juxtaposing the deadly tiger with the life-saving Savior of the world.
Similarly, Pi also sees the danger of the tiger. Though, interestingly, when the ship sinks and Pi is on the lifeboat and first sees Richard Parker swimming toward the lifeboat, Pi first sees the tiger as a life-saving companion, even begging him, "Don't give up, please. Come to the lifeboat. ... Swim, swim! You're a strong swimmer." It's not until Richard Parker is about to climb into the boat that it dawns on Pi he has just invited a tiger to share a lifeboat with him and tries to push him away and knock him unconscious with the oar but to no avail. Once the tiger is in the lifeboat, Pi next observes, "I had a wet, trembling, half-drowned, heaving and coughing three-year-old adult Bengal tiger in my lifeboat" (Ch. 37). Pi's observation juxtaposes the tiger's vulnerability with its ferociousness, much like Blake juxtaposes the tiger with gentleness and salvation. Later, once Richard Parker has eaten the zebra and hyena, Pi even describes Richard Parker as looking "catlike" and states he even misses Richard Parker who, once they landed in Mexico, disappeared into the jungle.
Hence, both the poet and the author are juxtaposing tigers' ferociousness with beauty and gentleness. Yet, Martel takes the analogy further since in the novel Pi is able to train and befriend Richard Parker.