Thorin is pragmatic in the way that all those who work with their hands are. Everything is about honesty and duty, although honesty is a lot more vague than people tend to give it credit for. He will be honest with those he respects, and he will show a certain amount of respect to almost anyone until they prove they are not worth it. To be worth respect, though, you have to be a hard worker, and you have to know when to work and when to play. That is one of the reasons he chose to work for Olaf out of all of those looking for an accomplished smith, and why he is so loyal to him, and by extension, Calder.
He also believes that true reality is tangible. Philosophy is fine for mellow nights spent around warm fires and cold beer, but when it comes down to brass tacks philosophers don't get the job done. And the only thing more rewarding than working is the satisfaction of a job well done. And a good bar fight.
He has little patience for whiners and less patience for dandys and fops. He has much more respect for someone who does their very best despite lack of talent than he does for a gifted artisan who squanders it.
He believes that something is worth doing then it is worth doing right, and that loyalty is such a basic need in society that it shouldn't need to be talked about, it should be taken for granted that everyone agrees and practices it. Being pragmatic lets him see that this isn't the case, a point which is a recurring aggravation.
He believes that family is sacred and that it must be protected above all, but while many feel it is blood that defines family, he believes that it is shared loyalty and friendship that truly define it.
He feels that the darkness needs to be fought and that the humans have lost their way and could use a reminder of what it means to be stalwart. He believes that if only the humans would do their part then the war would go better, but again he is pragmatic enough to know the odds. Putting down ones hammer and rolling up in a ball isn't the dwarven way, though, so he will be singing dwarven battle songs and drinking when he spits in Deaths eye for the last time. Anyone that does less is less.
But at the end of the day, when all is said and done, he would rather be left alone to work his forge and to shape the liquid fire that is molten metal into the very best tools, be they tools of trade or tools of war.
Nothing is more real than a hammer and anvil, and nothing more honest than fire.