These words designate thoughts or feelings about a subject. Opinion ranges from purely personal prejudice to relatively authoritative judgement. At both extremes it implies a prior formulation of ideas or conclusions regarding a matter in dispute or under consideration. At its most individual, it involves evaluation, indicating an expression of personal thought, feeling, preference or taste.

• What is your opinion of the latest styles?

In a more conclusive sense, it may represent an expert judgement in a matter of objective fact or truth.

• In the opinion of my doctors, I should be well enough to travel by next week.

In all cases, however, opinion is carefully distinguished from fact. An opinion may be held with confidence, but it still falls short of positive knowledge and is open to challenge.

• She sought the opinion of several experts, but even the experts disagree.

In a broader frame of reference, opinion may indicate prevailing ideas that many people hold in common: public opinion . At its most definite, it designates the formal announcement of the conclusions of a court: the majority opinion of the Supreme Court, citing precedents and constitutional principles in support of a decision.

Sentiment and view relate to personal opinion , and both frequently appear in the plural. Sentiment stresses feeling rather than reason, often indicating an idealistic approach or emotional stand rather than a pragmatic one. The word is now encountered only in certain contexts.

• His Anzac Day speech was full of patriotic sentiments ; the sentiment expressed on a birthday card; A clever barrister will try to assess the sentiments of a jury before launching his defence; I agree with you – those are my sentiments exactly.

View stresses the personal element, emphasizing an individual attitude, approach or point of focus.

• In my view , the scheme seems unworkable; an article setting forth the member’s view on Vietnam and the proposed tax increase; a naturalistic novelist’s view of society.

Impression and estimate stress the element of uncertainty in venturing an opinion. An impression arises from external factors, whether it leaves its mark on the senses or the mind. The word may indicate the first reaction of the mind, before the due consideration that warrants an opinion , and may imply a superficial view or conclusion: the danger of judging on the basis of first impressions . In other cases, impression may emphasize vagueness of recollection, or caution and uncertainty in stating a view:

• My impression is that she was lying, but I couldn’t swear to it; He had the impression that they had met before.

Unlike an impression , an estimate does not reflect an uncertain memory or mind; instead, it involves a personal appraisal or a value judgement. An estimate is based on the pertinent facts available at the time, the implication being that other, unknown factors might enter at a later stage.

• The final cost was considerably higher than the builder’s original estimate .

An estimate also involves a consideration of the different aspects of a thing, or a weighing of pros and cons, with the attendant possibility of error in judgement.

• After reviewing his first batch of work, what is your estimate of his ability?; a critical estimate of Morris West.

Belief and conviction are examples of positive opinion. A belief is something accepted by the mind as being true without certain proof. It may either originate in the mind or be instilled in the mind by others: a child’s belief that monsters lurk in the dark; a boy’s belief in Father Christmas. Belief has a wide range of application, embracing ideas, theories, philosophies, religious creeds or tenets, superstitions: a belief that men are basically good; the Christian belief that Jesus was the Son of God; the belief that Friday the 13th is unlucky. Belief , itself, may range from simply, unquestioning acceptance to deep emotional involvement: belief in a news report; belief in a friend’s innocence. Sometimes, however, it may convey a lingering uncertainty.

• It’s my belief that she’ll succeed, but only time will tell.

A conviction is a strong belief arising from a deep-seated feeling of certainty. The word often implies the overcoming of previous doubt or scepticism.

• Captain James Cook’s conviction that appropriate diet would prevent scurvy; to have the courage of one’s convictions .