TCS says that you should live morally, and you should live rationally, and these are essentially the same thing. Actually, I don't know how clearly that message is said. But who cares? *I* say that. And *you* should evaluate whether it's correct or not. You shouldn't obey TCS, like one follows the tenants of a religion. (You shouldn't *obey* a religion either.)
A lot of people would say it's obvious we should do what's right, and that they, and most people, already try. Partly they are correct, and that's why our society is much better than during the Dark Ages. But if we consider the basic steps required to do what is right we will soon discover they aren't all so common and popular. To do what's right you must have knowledge of what is right. To get that you must seek the truth. To do that you must be open to new ideas, and to criticism of your present ones, and you must be able to have *critical discussions*. You don't absolutely necessarily have to discuss with other people. You could read books at home. But if you do you have to simulate critical discussions in your head: you need to argue both sides of points that come up. If you only argue in favor of your own side, the book isn't going to respond very well. So either you need a lot of intellectual integrity to criticize your own ideas, or you need to enjoy to have other people do that for you. Or better, both.
A lot of people have somewhat different goals. Some want their present idea to be true. Some want to be happy. Some want all their conversations to be polite which includes hiding disagreement and therefore criticism.
If you want to be happy that can be fine. In fact it's very good if it means the right thing. If you have a choice between happy and unhappy, go happy. If you have a chance to seek happiness, or not, then seek it. etc. But if you have a choice between an option that appears to be best for happiness, and another that appears to be better for learning the truth of the matter, you must choose the truth, and many would not.
If you chose happiness over truth you get neither. You may well fool yourself and think you are happy. But that's no life worth living. If we wish to be fooled we may as well do it right: use hard drugs. And in the future use Virtual Reality technology to fool ourselves into believing we have the life we want. The only way to get a good sort of happiness is to know the truth, and to then be able to make an informed judgment about which lifestyles are good, and to enjoy and be happy about having a good one. Knowing more is no guarantee of happiness, but not knowing guarantees you have no way to make good choices so it doesn't even give you a chance.
Ever heard of "constructive criticism"? Of course you have. People all the time say they only want constructive criticism. Partly they have a point. Some criticism is of the form, "that sucks" which is pretty useless. Though I must say I don't see how one can really mind "that sucks" from a stranger -- what on earth do you have to feel bad about? He hasn't bested you in any sort of argument. He hasn't given a reason your work sucks, and therefore hasn't given you any reason to think it sucks. You should just disregard his unsupported assertion. But anyway many people don't want to hear such insults. I'd rather have a truer sense of what sort of people exist and how they react to my work.
But does wanting constructive criticism only rule out unsupported criticism? Not at all. It also rules out anything very harsh -- even if that is the most accurate and reliable way to communicate an important critical idea. It also indicates the author is fragile and that a long list of criticism will not be appreciated no matter how high quality every listed point is. It also means that if the work in question is in fact bad, and should be abandoned, the author doesn't want to learn that truth. The author only wants "constructive" criticism, ie focussed on how to improve it and not focussed only on pointing out flaws, no matter how important they are. Any reader who notices a flaw but doesn't want to take the time to provide the extra help of also finding a way to fix the flaw isn't able to offer "constructive criticism" and therefore must offer no help at all.
Constructive criticism is about hiding from the truth. Not fully hiding. Just partially. But that's what it does.
Why do people do it? One reason is that they take criticism personally. That's very bad. How are you going to find the truth if you are attached to certain ideas, true or not? We should let our ideas die in our place, not attach ourselves to them and die with them. Bad ideas must die. Our ideas might be bad. How should we know they aren't? People make mistakes all the time. If valid criticism comes then the idea is flawed. It must be changed or possibly given up entirely. That is best. We should be pleased. We were going down a dead end by mistake and now we know better and can avoid that fate. We have at least a chance of pursuing something good and being happy now, because we know more.
Taking things personally and being attached to debatable ideas obscures the truth. It makes it harder to understand the "opposing" side (they should not be seen as the opposing side. it's just a different side and you should dispassionately consider if it has a point). getting offended by things which say the idea you are attached to is wrong helps nothing. it doesn't make it easier to figure out objectively which idea is true.
So suppose you like what I say and agree with it in theory. What is needed to actually apply it in your life? Because it's common that people agree with philosophical ideas then thoroughly fail to actually follow through on them. So what are the important things to keep in mind for actually being able to objectively find the truth?
The first and perhaps most important thing to keep in mind is that there is far more to learn about the philosophy than I've said here. Even if you know more than me, you could understand all these things better. Learning more makes applying it easier and more effective.
Next, there is a sort of self-awareness that is very important. Many people assume that they understand themselves and know why they do things and that they choose to do all the things they do. This is very false. Many things people say about why they did actions are guesses, often very bad and thoughtless guesses. And often the reason for that is they did not have a reason when they did it -- they didn't think about it and choose what seemed best to do -- so there is no good answer to why they did it. But that's hard to admit. And hard to notice in the first place. I think it's worth mentioning this is partly caused by static memes, and those are very good at hiding themselves and being hard to criticize, and also causing emotional distress in those who do criticize them. But it's not just memes. Remembering things at all is guesswork. And finding the truth, including the truth about our own personalities, is hard, and requires being open to criticism and not being attached to particular ideas and not taking things personally and so on. People find that hard with their own personality above all!
So, self-awareness. If we pay close attention to how we live, how we feel, how we think, then we will be able to spot problems and to try to change them. We can notice we are sometimes thoughtless, which among other things means not carefully considering what's best and not carefully considering what is the truth of the matter, and if we get good at self-awareness we can notice *in real time* and then intervene and do something different.
Some people would find that scary. Notice their flaws? Then they have to admit to having them. Change personalities? Then they have to admit to being messed up so much they need to change. Really that's a harsh way to put it. No one is perfect. Imperfect people should change so they can get better. But people often think of it the harsh way. Regardless, noticing our flaws is the only road to getting rid of them. Knowing the truth is the only way we can move on to better things. While we might seem and feel happy in our ignorance we must remember those flaws are making our lives worse. All sorts of things we care deeply about are not working out as well as they could. Flaws make us less wealthy. They make it harder to get promoted. They make us hurt our children, and fight with our loved ones. They make us less able to help loved ones and friends in need who we want to help. They can make us less successful at everything we do. Now I'm not saying every flaw does all these things to a huge degree. But flaws do things like this. And how do you know what the bad effects are if you won't look honestly to see what your flaws are?
This thing about perfect and imperfect people brings up an interesting point. If we are imperfect do we really need to change? We might just have the tiniest little flaw. I would say every little bit counts. Being the best we can be means caring about even small improvements. But also the smaller the flaw the easier it is to change, so that's no reason to "not bother" or something. When people are scared of facing flaws they aren't thinking of tiny imperfections -- those aren't scary. It's big things that are definitely having a significant effect on their life.
What else can we do to get better at seeking truth? One important thing is asking questions a lot. People often think they understand things when they don't. People also often pretend to understand things to avoid looking ignorant. A friend told me that in Mexico if you ask for directions people will make them up if they don't know just to pretend they aren't ignorant. How can you tell if you understand well? Try to apply the idea to other issues. Or try to explain it to someone else. You don't need an actual person you can just imagine explaining it. And imagine this person asks questions about it. Can you answer them all? If so, fine. But if it's even a little blurry in your mind then you could understand better. You should be asking those questions so you know more about it. Really the only thing that *should* be embarrassing is *not* asking questions: that is just dumb. You have this opportunity to learn something, which you should be proud to do, it's part of a good and admirable lifestyle to try to learn all the time. And instead some would waste it on a different lifestyle: pretending they have nothing to learn.
Question asking isn't just a matter of being willing to ask. It's also sometimes a matter of seeking out people to ask. If you want to know something you can find someone to ask. And of course you can also find books to read, google it, and so on, and that's important too.
It's also a matter of skill. Often people aren't totally clear on a concept but also can't think of a question. They aren't sure what it is they don't understand well. But with enough skill we can quickly create lots of questions. Unfortunately it's hard to explain how to do that. You might try reading my series of dialogs starting with How To Ask Questions which attempts to provide a good example: Caeli asks a lot of questions.