## Using the Divide and Conquer Approach To Problem Solving

### Use logic to arrive at a conclusion.

To solve virtually any problem, you can use a process of elimination dividing the issue down until all you have left is the problem. There are four basic steps to this process:

1. Define the problem

2. Develop a plan

3. Implement the plan

4. Evaluate the results

Until there’s an acceptable answer, you’ll repeat steps 2 through 4 until that answer has been reached. We’ll use a common problem to illustrate this scenario.

### Define the problem.

Your car won’t start, there’s nobody around, and the mechanics of automobiles is a complete mystery to you. It’s a brand new car, so you are not familiar with it. Furthermore, you are going to be late for work if you don’t get your car started, so it’s up to you to figure out what the problem is. There are many issues there to deal with, but only one problem: your car won’t start.

When defining the problem, do not consider things that are extraneous matters, only what the actual problem is. You can consider the other issues later.

### Have a plan.

This is important to develop for solving any problem, and key for keeping the process on track and finding the solution in the shortest amount of time. For our example, the plan is straightforward though maybe not simple as a car is a fairly complex piece of machinery. The plan will be to break the issue down into smaller problems that are more easily solved, until we are left with the actual cause of the problem.

### Implement the plan.

We’ll start with big, obvious yes/no questions. Knowing what the problem isn’t is just as important as knowing what it is.

Does the engine turn over when you engage the starter? If it does, then the battery is not the problem, and you’ve eliminated one major possibility. If it doesn’t turn over, then we know the problem is probably electrical. For this example, we’ll say it didn’t turn over.

We know now that the trouble likely lies somewhere along the electrical path, whether it be starter or battery or some other electrical issue.

### Evaluate the results.

What did you learn from the first test? Did it turn over a couple times, then slowed down and stop? Did it only make a clicking sound? If it did that, the problem would likely be a dead battery. For this example, though, what happened was neither the starter nor the engine made any sound at all, and didn’t even attempt to start. This could mean a totally dead battery, except for the fact that turning the key caused all the dash lights and the radio to come on, just like normal.

Now we know that the battery seems to be OK, but something is still preventing the car from starting. So we know the problem is that power is not getting to the starter when you turn the key. That doesn’t help you get to work, though, so start again from step 2.

### Develop the next plan.

If you knew auto mechanics, you might look under the hood to see if all the parts were there. For this example, though, you wouldn’t know valve seal from a bivalve. Still, you look, see the engine is still inside, and nothing is obviously missing, so your next plan is to consult an expert the owner’s manual.

### Implement the plan.

Since you’ve narrowed the problem down enough to know it’s not a dead battery or no gas, you look in the manual for where the problem actually is: starting the car.

You note a large alert icon with text stating, For safety reasons, you must step on the brake pedal to start your car.

### Evaluate the results based on this new knowledge.

Did you press the brake pedal when you first attempted to start the car? If you did, then that’s not the issue. However, to make a long example bearable, let’s say you neglected to step on the brake pedal.

### Develop the next plan.

It’s getting easier, isn’t it? Your next plan is to attempt to start the car with the brake pedal pressed down.

### Implement the plan.

Attempt to start the car with the brake engaged.

### Evaluate the results.

Did it start? Yes, it did! Your problem is solved, and you’re on your way to work.

Had it not started, it might also be the point where you call in a real expert your auto mechanic. However, because of your methodical and diligent attempts to solve the problem, you will be able to give him a very good idea of what’s wrong, which will lessen the time it takes him to figure out what’s wrong, which will lower your bill.

In the next part I will discuss how brainstorming is a great way to break a problem down into pieces so a solution can more easily be determined.