Whether we need a teacher or not depends on circumstances.
The relationship between a teacher and a new subject is
somewhat similar to that between a tour guide and an unknown city.
When we come to an unknown city for the first time,
we definitely need a tour guide. We might have a detailed map,
but it is unlikely functional – it isn't surprised that we can hardly
interpret those mysterious symbols. Likewise, when we are beginners,
it is wise to learn with teachers. They can tell us where to begin with,
what we should do, and which reference we should choose. When we
confront difficulties, we can ask them for help, and their advices will always
be tremendously helpful. With teachers' assistance, we might learn easier,
faster, and more interestingly.
After a period of time, we have learned a lot. We now know the city pretty well,
even though there still are many places we haven't been. It doesn't matter.
Now that we are able to recognize those mysterious symbols on the map,
what we need perhaps is not a tour guide but a more detailed map. Similarly,
we need richer references for learning. Yes, there are still many fields unexplored;
they are, nevertheless, no longer puzzling. The task is simple: we will explore them one by one,
little by little. If we are working on a certain skill, practice more; if we are preparing a test,
practice more; whatever we are learning, just remember, like people always say,
practice makes perfect.
After another period of time, we might have become others' tour guide, but we still
want to know more. We want to know which restaurant is the most decent, which
bookstore is the most professional, which coffee shop is the most classical.
Even the most comprehensive map doesn't have adequate information.
We again need experts. In learning, it's much the same. We need experts
to consult for specific problems. Furthermore, the most beneficial merit of
consulting experts is that we can not merely refer to them but even discuss
with them in depth. As is often the case, a solution for a complex matter is
not waiting for us right there and then, sometimes it comes out of inspirations of discussion.
In short, having a good teacher is always better than having none, but the
importance of a teacher varies from period to period, from stage to stage.