There are two main types of reasoning in Philosophy, which are used to prove or disprove things. One of these is inductive reasoning, also known as a posteriori. Inductive arguments take evidence from the world around us to reach a certain conclusion. Here is a simple example:
1. The sun has risen every morning of my life.
2. Therefore, the sun will rise tomorrow.
This is the type of reasoning that humans use in every day circumstances, it is why we act the way we do. When I was younger, I stepped on a pin, and that pin hurt me when I stepped on it. Now, when I see a pin, I won't step on it, as I don't want to be caused pain. When I eat my breakfast, I don't have peanut butter on toast, as I didn't enjoy the taste of peanut butter when I had it previously. I want to enjoy what I eat for breakfast, and therefore, I have jam on toast, which I enjoy.
This type of reasoning is also innate to the animal kingdom, as animals have been seen to associate two things that have nothing to do with each other, just because their brain associates one thing with another. This is known as Classical or Pavlovian conditioning. The most famous example in the animal kingdom goes like this.
When my dog sees food, he begins to salivate as it is an instictive response as it helps dogs break down their food.
When my dog hears a bell, he does not begin to salivate, as he doesn't believe that there is any food he needs to break down.
If I regularly ring a bell before I give my dog food, he consciously associates the bell with food.
When I ring a bell, my dog begins to salivate.
This example allows us to see the problems with inductive reasoning. Just because we associate a certain thing, (a pin, peanut butter, a bell) with a certain experience or emotion (pain, disgust, excitement for food) it does not mean that we will experience this emotion if this thing happens. The example in the animal kingdom shows the issues with inductive reasoning, as, I could ring a bell, and my dog starts salivating, but does not receive food. As my dogs reasoning and my own reasoning are the same, does this show that there is an issue with inductive reasoning in itself. How do I know that the sun will rise in the morning, just because it has risen every other day of my life? My dog hears a bell every time they receive food, yet the bell and the food are independent of each other. Does that mean that a day of my life may go by in which the sun does not rise?
The question that we are asking here is: Will future futures resemble past futures? One assumption that naturally we make is that the oftener things happen together, the more probable is that they will be found together another time, and if they continute to be found together we can almost certainly say that they will be found together always. The issue here is that we are never able to be completely certain about any knowledge obtained from the empirical world. We can never be certain, as, no matter how many times we find two things together, there could be a final situation in which they are not associated, and therefore, it will not happen. In this way we cannot know, with absolute certainty, that the sun will rise tomorrow. This is the issue with inductive reasoning.
Since we have found that we can not have absolute certainty in anything by using inductive reasoning, we should move onto the second form of reasoning. This reasoning is a priori or deductive reasoning. It is the process of reasoning used to reach conclusions with absolute certainty. One or more premises are presented that present a logical conclusion. Here is a well-known example:
Premise 1: Socrates is a man.
Premise 2: All men are mortal.
Conclusion: Socrates is mortal.
Although, these arguments are capable of falling to a range of fallacies if used incorrectly, and it is important to avoid these fallacies if we want to use deductive reasoning effectively. Here is an example of a deductive fallacy.
Premise 1: All dogs are mammals
Premise 2: All cats are mammals
Conclusion: All dogs are cats
This is clearly incorrect, as shown by this diagram, which I have drawn very poorly.
Another issue with deductive reasoning is that we can produce valid arguments, with no fallacies, but with untrue premises. For example:
Premise 1: If the Earth is round, then things would just fall off it.
Premise 2: Things do not fall off the earth.
Conclusion: The Earth is not round.
This is a valid argument, but the conclusion is certainly not true. This is because the premises are untrue. Premise 1 is untrue as gravity pulls things to the earth so that they don't just "fall of the earth". An argument with true premises must have a true conclusion.
So surely, this is how we know things for sure, if we produce these true premises. The issue is producing these true premises. Surely we have to use inductive reasoning to produce premises that will produce a sound argument. To take our initial premises with our sound argument: All men are mortal. Are all men mortal? I am a man, yet, I have not died. All things that are immortal do not die. I have not died. Does that make me immortal.
Premise 1: We can not, with absolute certainty, prove anything is true.
Premise 2: To know something is to be absolutely certain or sure about anything.
Conclusion: We cannot know anything, apart from that we don't know anything.
Comments