In "Walden" by Henry David Thoreau, there are examples of both inductive and deductive reasoning throughout the text. One particularly effective example of deductive reasoning can be found in the chapter titled "Economy." Thoreau argues that people often live beyond their means, accumulating unnecessary possessions and living in excess. He then uses deductive reasoning to support his argument, stating that "the cost of a thing is the amount of what I will call life which is required to be exchanged for it, immediately or in the long run."
Thoreau's deductive argument is effective because it is logical and easy to follow. He starts with a general statement about living beyond one's means, then uses deductive reasoning to explain why this is a problem. By defining the cost of a thing as the amount of life required to exchange for it, Thoreau gives readers a clear and compelling reason to avoid excess and unnecessary possessions.
Overall, Thoreau's use of deductive reasoning is effective because it helps readers understand the importance of living a simple, minimalistic lifestyle. He presents a logical argument that is easy to follow and understand, making his message all the more powerful.