Advance, promote, forward and further all mean to move or put ahead, but they come into comparison chiefly when they imply help in moving or putting (something) ahead.
Advance usually implies effective assistance, as in hastening a process.
- the warm rains greatly advanced the spring crops
Or in bringing about a desired end.
- the pact should advance peace among nations
Or in exalting or elevating a person, especially in rank or in power.
- Ahasuerus . . . advanced him . . . above all the princes
The implication of moving ahead is dominant in promote when the word means to advance in grade or rank, especially in a predetermined order.
- promote a pupil to the next grade in school.
- promote a member of a college faculty from associate professor to full professor
When the dominant implication is assistance, promote may suggest open backing or support.
- the objects for which a corporation is created are universally such as the government wishes to promote
It may, especially when the subject names a person, his influence, or his acts, imply actual advance by encouraging or fostering.
- a sound forest economy promotes the prosperity of agriculture and rural life
It may, when said of a thing such as a practice, a policy, a habit, imply subservience to an end that may not be intended.
- the habit of regarding the language of poetry as something dissociated from personal emotion . . . was promoted by the writing of Greek and Latin verse in school
In one or two collocations forward implies not assistance but effective carrying out.
- forward a shipment by express
- please forward all letters during my absence
In its more common sense forward is often not clearly distinguishable from advance, except that it is seldom if ever used with reference to persons.
- Marie de Médicis had advanced Marillac by marrying him to one of her maids of honor . . . yet . . . she only forwarded the marriage because she wanted to do the girl a favor
Further, less than any other word in this group, implies movement ahead and, perhaps more than any other, emphasizes the assistance given, especially in the removing of obstacles, either to a person in an undertaking or to the project he undertakes.
- her sole object. . . was to further him, not as an artist but as a popular success
- bodies like the French Academy have such power for promoting it [genius], that the general advance of the human spirit is perhaps, on the whole, rather furthered than impeded by their existence
— A mold