Implant, inculcate, instill are comparable when they mean to introduce into the mind.
Implant usually implies teaching, and it stresses the fixedness or permanency of what has been taught.
Inculcate implies persistent or repeated endeavor with the intent to impress firmly on the mind.
Instill carries the implication of a gradual and gentle method of imparting knowledge; it usually suggests either a teaching that extends over a long period of time (as from infancy to adolescence) or a pupil that cannot, because of age, lack of background, or the like, take in at once what is taught.