The scientific method is the best available method for learning about our universe, and even ourselves.
Science is not just a particular field of study like chemistry or physics. Instead, it is a method for asking questions, and systemically examining possible answers in an effort to discover which ones are more accurate. Because science is a method rather than a particular opinion or fact, it is universally applicable, but also the current answers identified as best by the scientific community are subject to change as we ask more and better questions about those answers.
This changeability is one of the benefits, not a flaw, of the scientific method. It gives us the flexibility to always learn more, rather than arrogantly assuming we know everything there is to be known about a topic. Even though scientific consensus about a question may evolve over time, it is still reasonable to consider some answers wrong, or significantly worse than other answers.
For example, consider the shape of the Earth. Anciently there may have been many people who assumed the Earth was flat due to its perceived flatness from human height above the ground. This answer is clearly worse than the answer that later but still ancient mathematicians were able to devise, concluding that the Earth was perfectly spherical. Even this knowledge was not perfect, as we now understand that a better answer to the shape of the Earth includes the slightly "squashed" height of the polar axis compared to the equatorial diameter. Clearly this answer is more accurate than any of the answers that came before it, but still does not account for the actual variation in local altitude across the globe.
Despite the many different answers that this scientific cycle has provided by questioning, and then questioning the answers; it is clear that not all answers are equal. Changing opinions in the scientific community does not mean that a flat Earth is a reasonable opinion. In order to conduct good science, whether in fields of geology and astronomy, or in philosophy and psychology, we must be humble enough to accept new and better answers into our lives.
Tools for analysis
There are two main branches of analytical thought: inductive and deductive reasoning. These two methods compliment each other to help us create logical understandings of the world we inhabit. Knowing the strengths and weaknesses of each can help us utilize them more effectively in our daily lives.
Inductive reasoning is to build on previous knowledge to reach new, but likely conclusions. For example if you know that John went to the grocery store, you could probably induce that he bought groceries while he was there. It's not guaranteed, but it's not an unreasonable conclusion either, given the available information. Induction is useful when we only have limited information about a topic, and are trying to build a general framework of understanding about that topic.
Deductive reasoning is to critically examine previous knowledge, in order to eliminate untrue conclusions. This form of logic was made famous by Sir Arthur Conan Doyle's character Sherlock Holmes who said, "when you have eliminated the impossible, whatever remains, however improbable, must be the truth". For example, if we know that John bought some kind of food at the grocery store, but we know he didn't purchase processed foods, or food that came in any kind of packaging, we might deduce that he bought fresh produce while at the store. This conclusion depends on having accurate information about what was not the case, as well as having considered all possible options, which is a daunting and time consuming process. For this reason, deduction is useful when we have a great deal of information about a topic, and are trying to develop a detailed and absolutely correct understanding.
The cycle of exploration
The scientific method takes advantage of both of these forms of logical analysis. First, a question is posed, about anything. Then inductive reasoning is used to propose a hypothesis; creatively imagining a possible solution that logically follows from the existing information. Next, deductive reasoning is used to attack this hypothesis, actively seeking to disprove the hypothesis. If the hypothesis is disproved, the scientist returns to inductive reasoning to suggest a new hypothesis within the bounds of whatever limits deductive reasoning revealed. If the hypothesis has not yet been disproved after exhaustive deductive critical reasoning, the scientist also returns to inductive reasoning to suggest further information that would be true if the hypothesis is true. Deductive reasoning is then used to attack this additional hypothesis, and if it successfully disproves this hypothesis, the original one might be called into question once more. This process continues endlessly, returning new and more accurate information than was available in previous cycles. For this reason, the scientific method is considered the best available method for learning about the universe: it is testable, logical, and has an excellent track record of improving the human condition.