Laymen often have trouble understanding science, or the answers scientists provide to their questions here on PF. If you are one of those people, I have a very simple suggestion for how to start thinking like a scientist and understanding key concepts. All you need to do is to purge your brain of three wrong ideas. 1) All questions do (or should) have answers. Personally, I never wasted two seconds worrying about unanswerable questions, but many people find that very disturbing. Some resort to philosophy or religion for those answers. The meaning of life is a prime example. What existed before the Big Bang is another. So when you learn that your question has no answer (and maybe never will) shrug your shoulders, stop worrying about it, and resist pointless speculation. 2) Do not fixate on the exact meaning of words. The age of natural philosophy truly became the age of science, when the practitioners leaned to stop fixating on the meaning of words in natural language. Biggest among such words is infinity. One of the biggest arguments in the history of science was irrational numbers (such as 1/3 = 0.33333 with an infinite number of threes). If you think about infinity too much (especially infinities in space and time) you can quickly imagine preposterous absurd things. I recently heard a debate over science versus religion where the speaker tried to use absurdities of infinity as proof of God. Stop wasting your time doing that. Our brains are not wired to be able to visualize all things or to relate them to everyday life by analogy. Scientists are forced to use natural language even when the meaning of the words they use are an imperfect match for their message. Learn to accept that. 3) Forget the ordinary meaning of simultaneous. Until Einstein's 1905 paper on special relativity, all of his predecessors made the same error. They assumed that observers could synchronize watches regardless of location and motion, and agree on the meaning of simultaneous. Einstein's big breakthrough was to realize that he needed a different definition of simultaneous, and that ovservers in different frames can never agree on the simultaneity of events. Internalize Einstein's definition and it will open up a whole new world for you. -- I'm sure that PF commenters can add new things to the list, but IMHO these three are the big ones.