Either of those can come first. What is important is that the other should follow. You might read an interesting quote, be told about a good investment, develop a liking for something, want to take an impulsive decision…; since these all are controlled by left brain, it is necessary and helpful to support it with proper logics.
On the other hand, you might have finished with lot of theory, attended an interesting talk, read a news article, read a good book…; these are processed by right brain. To get accustomed to them, one needs to apply them practically and develop it as a part of left brain.
To summarize, if a new thought / idea comes, then develop logics. And if a new thing is learnt, then try to develop a mental model for it.