Angel Clare is an apprentice gentleman farmer who is the son of an Evangelist minister who had at some point wished that Angel would follow his steps of attending Cambridge and obtain a parsonage of his own. Although he is seen by the lower folk as an intellectual man who is
“too much taken up wi’ his own thoughts to notice girls.”
However, it seems as if Angel Clare's intellect gets the best of him. In chapter 18 we notice how he blatantly refuses to believe in the Anglican Church's tenets on the resurrection, and even laughs at the idea of a resurrected Christ in body. We also see in these chapters that Angel Clare is no stranger to trouble. He has an affair in London that was mucky enough to almost get him to marry the older woman whom he romances, and he simply seems to idealize just about everything he knows. In Hardy's words to express Angel behavior, he says that
he was ever in the habit of neglecting the particulars of an outward scene for the general impression
Therefore, although Angel is intellectual he does not seem to enjoy the benefits of having a well-grounded common sense for things.
What attracts Angel to Tess is that, again, her naive and innocent ideas of life make her an easy target to idealize. It is Spring now, and Tess seems to be in tandem with her surroundings. She experiences a number of feelings quite bucolic and fantastic for a regular person to feel. The words that come out of her mouth are precisely what separate Tess from the rest of the milkmaids, and what gets the attention of Angel.
The irresistible, universal, automatic tendency to find sweet pleasure somewhere, which pervades all life, from the meanest to the highest, had at last mastered Tess. Being even now only a young woman of twenty, one who mentally and sentimentally had not finished growing, it was impossible that any event should have left upon her an impression that was not in time capable of transmutation.
When Tess exclaims her passion for the season, Alec sees clearly how different she is and claims that she is an innocent daughter of Nature. In his eyes, she is like a Virginal sample of life itself.
What a fresh and virginal daughter of Nature that milkmaid is!
We know that, after they marry and he finds out about Alec, the relationship deteriorates and he takes off to Brazil. It only took that one fact for him to completely remove his feelings for Tess. She is no longer a virginal creature, hence, she is no longer his ideal.
Therefore, we see in Angel Clare a man without a sense of direction, with a lot of intelligence, but with little application of it for the things that truly matter. He is a dreamer and an idealist. He is nothing more nor nothing less than an abstract thinker, and not at all a realistic individual.