From The Collaborative International Dictionary of English v.0.48:
Conduce \Con*duce"\, v. i. [imp. & p. p. Conduced; p. pr. &
vb. n. Conducing.] [L. conducere to bring together,
conduce, hire; con- + ducere to lead. See Duke and cf.
Conduct, n., Cond.]
To lead or tend, esp. with reference to a favorable or
desirable result; to contribute; -- usually followed by to or
toward.
[1913 Webster]
He was sensible how much such a union would conduce to
the happiness of both. --Macaulay.
[1913 Webster]
The reasons you allege do more conduce
To the hot passion of distemper'd blood. --Shak.
Syn: To contribute; aid; assist; tend; subserve.
[1913 Webster]