Deduction, induction, + syllogism.

"For in ordinary logic almost all effort is concentrated on the syllogism. The logicians seem scarcely to have thought about induction. They pass it by with barely a mention, and hurry on to their formulae for disputation. But we reject proof by syllogism, because it operates in confusion and lets nature slip out of our hands" (Bacon, The New Organon, 16).

In the Preface and "Plan of 'The Great Renewal,'"Bacon is laying the foundation for a new method of inquiry that will correct the mistakes that all philosophy and science currently rests on. He believes that the very foundation, the bedrock if you will, that the house is built on doesn't exist. It essentially floats in the sky (the example he uses is a palace floating without a foundation). The core of his new mode of inquiry is the use of inductive reasoning versus the prior use of deductive reasoning. Therefore, I thought it might be a good idea to try to explain or work through these two methods of logic and figure out why Bacon so favored one over the other.

Deductive reasoning is based upon the categorical syllogism, which is a kind of logical argument where the conclusion (a proposition) is inferred from two or more other propositions (the premises). A common example of a syllogism is this:

All men are human.
All humans are mortal
Therefore, all men are mortal.

Deductive reasoning is also called "top-down logic." In this process, one or more general statements is used to reach a logically certain conclusion. Another example is this:

All philosophy classes are hard to understand.
This class is a philosophy class.
Therefore, this class is hard to understand.

Inductive reasoning (also known as "bottom up logic") is the kind of reasoning that constructs or evaluates general propositions from specific examples. This contrats with deductive reasoning where specific examples or generated from general propositions. Inductive reasoning is probabilistic. An example I found on the internet is this:

All life forms that we know of depends on liquid water to exist.
All life depends on liquid water to exist.

In this example, the possibility exists that there could be a life form in the future that doesn't depend on liquid water to exist but historically all life does depend on water to exist.

So what does Bacon think the inherent value of inductive reasoning is versus deductive reasoning? That I am not entirely sure of. I think it may be that inductive reasoning is better because one goes from specific facts to general conclusions rather than general conclusions to the specific. Also, maybe he values inductive reasoning because it leaves open the room of probability, whereas if one were to be deductive all the time then that doesn't leave open the possibility for error. Take this logically valid deductive argument for example:

All people who are smart go to Rhodes.
James is smart.
Therefore, James goes to Rhodes.

Logically, this argument makes sense in terms of its structure but clearly the first premise isn't true so it's not a sound argument. Maybe this is why Bacon detests deduction so much? It's better to prove generalities from specific examples rather than state generalities first.

Do you have anything to add or to clarify in this? It's been a while since I took Logic. What do you think the values of induction versus deduction are (or vice versa)?