These words mean to apply one’s mind to a subject in order to learn about it, to resolve any questions it poses, or to reach a decision concerning it. Study implies a careful attempt to learn all the aspects of the subject or problem under scrutiny before making plans or taking definite action.

• Meteorologists study information sent back to earth from weather satellites before making forecasts; A city council studies proposals submitted for urban redevelopment.

Consider is a more general word than study ; it can imply either momentary and casual attention given to something, or deep, prolonged concentration: considering whether to catch the bus or have another drink and wait for the next one; considering how much insurance he would need to guarantee the education of his children. Consider may point also to an objective judgement that has been reached after careful study : We are considering you manuscript for publication, but feel it needs extensive rewriting.

Contemplate implies thinking about something, as for a long period of time, but usually simply for its own sake and with no definite, pragmatic end in view: For a year we contemplated the possibility of living in the country. In its related meaning of looking at intensely, contemplate suggests leisurely and pleasurable reflection: He contemplated the Archibald Prize entries for an entire afternoon. In a more general sense it approximates one usage of consider. A course of action we could not contemplate.

Ponder and weigh both mean to examine all sides of a question in one’s own mind in order to make a careful evaluation. These words differ from study in that they emphasize the making of a choice between conflicting data, opposing claims or the like, rather than the acquiring of knowledge by searching into a body of information. Ponder suggests that the matter is a serious one and deserves careful deliberation: Before casting his vote, a responsible, mature citizen should ponder his choice of candidates. Weigh may be applied also to important considerations: The judge advised the jury to weigh the arguments and evidence presented by the prosecution and the defence. When the decision to be made is of minor significance, weigh is to be preferred to ponder : to weigh the advantages of going to the beach or to a cricket match on a hot day.