One of the mantras preached by Galileo and the western scietific tradition is that the goal of science isn't to explain things, but to describe things. When it gets down to scientific exploration of an idea like gravity, Galileo didn't simply try to divine the meaning of gravity, he simply measured it. Scientitists still don't have a good explanation of why gravity exists, but are very good at describing how it behaves and how to measure it. A good scientist doesn't just blathering about theory, but spends time investigating and trying to learn about things.
One of the results of the Kantian/Hegelian/Marxist revolution has been to turn this process of scientific inquiry on its heads. The Kantian tradition isn't content with description, but tries to divine explanations for things. In generates an impression that there are hidden reasons behind actions, and it trains people to look at all events for motives and reasons.
Time and time again in history, efforts at explanations have failed, while the efforts at simply creating accurate descriptions have resulted in discovery upon discovery. Those tending to seek explanations have a nasty habit of bending facts to their ends, while those concentrating on the accuracy of the facts tend to come out with a better understanding of what is and what is not.
People who bend facts often turn into tyrants. They get everyone caught up in their game of the big lies, while they push people further and further from the truth. Dialecticians tend to become dictators as their games turn more and more away from finding truth and turn more and more toward manipulating others.
One of the most damaging tricks of the German idealist dialectics is the process of assigning base motives to your enemies and high motives to your friends. It is really easy to assign motives to others, and when you get everyone in the game of questioning other people's motives, the dialectician can often weasel their way into power.
Think about office gossip. Why did Jack say good morning to Jill? He didn't say good morning to Jane! (The answer might be that Jill's desk faced the door, Jane was on the phone, Jack and Jill happen to be friends, but you can also assign motives to Jack. He was trying to get sex, or was bucking for promotion, or is trying to manipulate Jill.)
People used to teach that men should open doors for women. I remember a great deal of debate in school about the ulterior motives men had for opening doors for women. The teacher was convinced that it was a horrid form of oppression. Men opened doors for women as a matter of politeness and respect. Assigning the act a base motive can acheive the goal of denigrating your enemy.
Instead of talking about what people do and how they behave, the dialectic gets people into this act of questioning motives.
Of course, to make the dialectical questing of motives more entrenched the dialectician teaches his students that their every action has a motive. While studying education theory, my professor emphasized that every action of a teacher is either a praxis in the revolution or an act of oppression (This is the central theme of Friere's Pedagogy of the Oppressed). A teacher must always consider the impact of their actions and whether their actions will advance social cause or continue the tyranny of the American system.
The professor's world view created a nightmarish world where there was a dubious motive behind everyone's actions, and he re-inforced his world view because he had conciously assigned ulterior motives to his actions.
The scientific system where we simply look to describing the world, and not trying to explain it has provided us with a lot more than the dialectics of hidden motives.