What's the Main Idea?
Think of the main idea like a thread that's woven throughout the canvas of a written work. Though it may sound like a daunting concept, the main idea of a text is just the central purpose the author has for writing. This point may be as simple as illustrating, in easy-to-understand instructions, the laws of the road in a driver's education handbook. It may also be a little more complicated, such as Abraham Lincoln's famous Gettysburg Address, in which he declared his main idea 'that all men are created equal.' Often, non-fiction writings such as speeches or memoirs (a personal account written for the purpose of sharing significant events in one's life), contain more than one main idea because the writer or the speaker needs to address multiple points within the same work.
Finding the Main Idea
Usually, the main idea will appear somewhere in the first paragraph, though this is not always the case. Most of the time, there are three distinct sections in a piece of writing: the introduction, body, and conclusion. The introduction is where the author will present the main idea and perhaps provide necessary background information. Then, the body of the piece is made up of the paragraphs in the middle. This is where the author will give more details to support the main idea. Finally, the conclusion is where the author will tie all the details together and remind the reader about the most important part of the written piece: the main idea. In short, while the main idea should appear in the introduction, it should also be the most often discussed topic or idea throughout a piece of writing.
Let's take a look at Abraham Lincoln's Gettysburg Address to find the main idea. He begins with the following sentence: 'Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.'
Right away, we know that the Gettysburg Address is about liberty and equality.
Next, he says, 'Now we are engaged in a great civil war, testing whether that nation, or any nation so conceived and so dedicated, can long endure.'
The first line of the body does not use the words 'liberty' or 'equality,' but we know that the Civil War was fought to gain liberty and equality for all Americans; therefore, we can infer, that is, we can find meaning in Lincoln's words even though he is not saying it obviously, that the main idea of liberty and equality appears in the body of this speech.
Finally, Lincoln ends his speech with the statement that 'this nation, under God, shall have a new birth of freedom.'
Again, he is not explicitly using the words 'liberty' and 'equality,' but 'freedom' is a synonym of 'liberty,' and this 'new birth' indicates that slaves will be newly freed. So, while it does take a little bit of effort on the part of the reader, one main idea can be seen throughout Lincoln's speech.