what is the role of temptation and how does it influence the characters dicisions?

The role of temptation is a prevalent theme in The Island of Dr. Moreau. His experimentation begins as an indulgence; is it possible to create a series human-animal hybrids? Can they be educated? Civilized?

The use of skin, bone, and organ grafting- combined with the process of blood transfusions is a technical process. The more successful he is in his endeavor, the greater his desire becomes to further his experiment. For Moreau, it's not about moral rights or wrongs; it's about the technical challenge, the scientific process, and it's the technology that becomes his temptation.

He believes his project to be, “Nothing very dreadful really — to a sane man,” which is a most revealing statement, and even worse he seems to enjoy it. “You cannot imagine the strange colourless delight of these intellectual desires. The thing before you is no longer an animal, a fellow-creature, but a problem.”

Moreau's obsession with his subjects leave him no room for thought about what the eventual consequences will be. His quest in itself becomes his temptation, and the fact that he gives no thought to its consequences defines his fall to that temptation.