How is stryver selfish?

Stryver is an ambitious Lawyer who although he wins the court cases with his mouth, he is too lazy to think of strategys himself to win a case and relies too much on his team partner Sydney Carton who does the observing. Whilst defending Charles Darnay in court, Carton throws a note to Stryver to mention the similarity bewteen Carton and Darnay to which Stryver does so. When Darnay is released, Stryer takes all the credit for the victory and does not even mention Carton.