Why can't Dimmesdale see that chillingworth is his enemy?

Question

Its from the Scarlet Letter

Answer 1

Chillingworth's love of learning and intellectual pursuit attracts Dimmesdale. In the New World, men of learning were rare. Hawthorne says, “there was a fascination for the minister in the company of the man of science, in whom he recognized an intellectual cultivation of no moderate depth or scope; together with a range and freedom of ideas that he would have vainly looked for among the members of his own profession.” This love of wisdom is what will draw the two men together, thus facilitating Chillingworth’s plans.

Answer 2

name change, I guess
http://en.wikipedia.org/wiki/The_scarlet_letter#Plot_summary