A particular opinion may relate to subjective issues for which there are no conclusive conclusions, or it may deal with facts that must be challenged by the logical error of entitlement to one`s opinion. The distinction between facts and opinions is that facts are verifiable, that is, they can be accepted by expert consensus. One example is: “The United States of America was involved in the Vietnam War” versus “The United States of America was right to interfere in the Vietnam War.” An opinion can be supported by facts and principles, in which case it becomes an argument. Sources whose authors only intend to persuade others will not satisfy your need for information for an answer to your research question or evidence to convince your audience. This is because they are not always limited to facts. Instead, they share their opinions with us without backing them up with evidence. If you used these sources, your readers will notice your argument and won`t believe it. The reason you need this type of resource when trying to answer your research question or explain that answer is that all of these characteristics add credibility to the argument you`re making with your project. You and your audience will simply have an easier time believing – having more confidence in the argument – if you include these types of sources.
To make your writing interesting, you need to develop a controversial thesis. Sometimes you`ll write to convince others to see things your way, and sometimes you`ll just express your strong opinion and lay out your argument. Different people may draw opposite conclusions (opinions) even if they agree on the same facts. Opinions rarely change without new arguments being made. It can be argued that one opinion is better supported by the facts than another by analyzing the supporting arguments.  You can read the fourth chapter of Schaum`s Quick Guide to Writing Large Research Papers as an E-Book in our online collection, click on the title to open it: “How to write a thesis statement?”. Sometimes writers have a combination of goals, like when a marketer decides they can sell more smartphones with an informative sales video that also entertains us. The same goes for a singer who writes and performs a song that entertains us, but that she wants to offer for sale. Other examples of versatile authors appear in most scholarly writings. Do you need to refresh the differences between facts, objective information, subjective information and opinions? In occasional use, the term opinion can be the result of a person`s perspective, understanding, certain feelings, beliefs, and desires. A “judicial opinion” or “court opinion” is an opinion of a judge or group of judges that accompanies and explains an order or decision in a controversy before a court. A judicial opinion generally sets out the facts that the court has accepted as established, the legal principles by which the court is bound, and the application of the relevant principles to the recognized facts.
The purpose is to set out the court`s reasoning for its decision.  Subjective – Subjective information represents the views or interpretations of an individual or organization. Subjective information can be distorted or reflect educated and enlightened thinking. All opinions are subjective, but some are more factual than others. Scientific opinions may be “partial, temporal, contradictory and uncertain”, so there may be no accepted consensus for a particular situation. In other circumstances, a particular scientific opinion may conflict with consensus.  “Science advice” may reflect opinions on scientific concerns as expressed by one or more scientists or published in reputable scientific journals or textbooks, both of which require peer review and rigorous professional review. It may also refer to opinions published by professional, academic or governmental organizations on scientific discoveries and their potential implications.
*In this quote, it is mainly the “should” that makes it subjective. The objective version of the last quote would read as follows: “Studies have shown that women who start taking calcium in their 30s show greater bone density and fewer effects of osteoporosis than women who have not taken calcium at all.” But perhaps there is other data that shows complications related to calcium intake.