Thought leads and fire backs it. You reach a conclusion carefully and then defend it with more heat than the careful process would suggest, which catches people off guard.
You are hard to beat in an argument because you did the reading and you also actually care. The blind spot is that the caring arrived after the conclusion, and it makes changing your mind cost more than it should.
A beacon is only useful if it is pointed somewhere. Yours usually is. Every so often it is worth checking whether you are lighting the way or just being very bright at someone.