IF P, THEN Q
P
---------------
Q
Below are three different applications for which Modus Ponens is used.
1 - Example using common statements (premises) to arrive at a truth (conclusion)
Suppose while out fishing on a lake I tell you, "The key to catching fish is finding the right lure to use. " After trying various lures, I begin to catch fish. I then yell out triumphantly, "I have found the right lure to use!"
2 - Example using computer code to show logic operations
Back in the day I wrote programs in Java for Artificial Intelligence applications. Many times I would have to write a block of code that checked to see if two number objects matched, and if so, another sub-block of code would be executed. If the numbers didn't match, the sub-block of code was never executed. Here's an example:
if
(parent1.fitnessLevel == parent2.fitnessLevel)
{
mutation.count = 1;
return true;}
else return false;
3 - Example using a scientific hypothesis and scientific method
For a Botany experiment I decided to take cuttings from a Rubber tree (I did not know its actual genus) and plant them to see if or how long it would take for the cuttings to grow roots. I divide them up into two separate groups. Group one cuttings were soaked - cut ends - in a pail of "willow tea" water before being planted into dirt, while group two was planted directly into dirt. My hypothesis was that the vitamin-B1 found in the "willow tea" water would promote faster root growth on the soaked cuttings. After a period of time I dug up the cuttings and compared the root growth of the two groups. I found that group one had better root growth over group two.
Now that Modus Ponens is understood, let us look at how we can manipulate these types of arguments in our favor. As stated above, Modus Ponens works with valid arguments (refer to the P & Q formula above). A sly way of arguing is to use invalid arguments called fallacies. Since Modus Ponens can affirm the antecedent, to error in fallacy is to deny the antecedent.
IF P, THEN Q
NOT P
---------------
NOT Q
When you deny the antecedent, you are essentially arguing that there is only one cause to an event, when logically there may be several causes. Here is an example to better understand how to use this fallacy to your benefit during arguments:
If I drive fast, text while driving, or tailgate other vehicles, I will eventually have a wreck. Since I have stopped driving fast, given up texting while driving, and no longer tailgate other cars, I will not have a wreck.
This is obviously a fallacy. Here I am arguing that specific reckless actions will lead to a vehicle accident, which is a perfectly fine premise. However, I then fallaciously argue that by no longer practicing these three specific actions I will definitely have no wreck. Just thinking of all the different ways one can wreck a vehicle - slick pavement, drunk driver, deer crossing the road, etc. - it is obvious that giving up those three specific actions will reduce my chances, but there is no guarantee that I will not have a wreck.
~Deion "Mule" Christopher
