Rational thinking can be a good thing. But if someone goes to the extream it is not right. Because in rationalism only the censory perception is accepted as true. But we should understand that there are many parameters around us that cannot be senced to our human perception.
For an example we cannot see (sence) radio waves. But it exists and we use it. If Marconi thought that there are nothing as radio waves because he could not see a wave going between the two places, there will not be a radio technology or no E communication.
Science is developed through many hypothesis. In mathematics also many theories are developed through hypothesis. If someone becomes an extream rationalist there will not be a difference between computors and rationalist.
The ability to make dream thoughts and hypothesis is the remarkable ability of humankind. Scientists Inventors (the true creators of this world) made this world with making their dreams true. They have faced many troubles from rationalist extreamists. Before the first TV is made if someone said that we will be able to see a far away incident as it is through a window pane and record it to see later, most of the people would say that he is insane, because they have not developed their mind to think that anything has a possibility to happen.
People who don’t know much Science thinks that Science is always being Rational and they can get an “invention” if they mix the right formula in a test tube. But who invents the “right formula” just “hoping” that he will get the “expected” result…