what evidence does shelly provide of the creatures innate goodness

The creature wishes the neighbors to be happy and free of worry even if he can't be accepted by them. This is proof of his innate desire to do good and be a part of society; it also represents his connection to the humanity surrounding him.

"Observing his neighbors for an extended period of time, the monster notices that they often seem unhappy, though he is unsure why. He eventually realizes, however, that their despair results from their poverty, to which he has been contributing by surreptitiously stealing their food. Torn by his guilty conscience, he stops stealing their food and does what he can to reduce their hardship, gathering wood at night to leave at the door for their use.

The monster becomes aware that his neighbors are able to communicate with each other using strange sounds. Vowing to learn their language, he tries to match the sounds they make with the actions they perform. He acquires a basic knowledge of the language, including the names of the young man and woman, Felix and Agatha. He admires their graceful forms and is shocked by his ugliness when he catches sight of his reflection in a pool of water. He spends the whole winter in the hovel, unobserved and well protected from the elements, and grows increasingly affectionate toward his unwitting hosts."