Anyone who says "you can't learn X by thinking about it" either does not know X himself or is using the English language in a clumsy fashion by selectively considering some forms of thinking to somehow not count as thinking.
If there's any experience about it in your head (and there will be if you come to learn it) it is thinking.
In my opinion the capacity to think is required in order to learn, therefore I believe thinking is a prerequisite to learning. On the other hand, I believe it is possible to learn about something without having thought about it previously. This would be in response to an unanticipated observation and would still require that the person be thinking as they are processing what they have observed. In this case, thinking and learning would be concurrent processes. At a very basic level, an organism has to be capable of thinking about something in order to learn about it.
Learning requires thinking. If a creature without a mind, and thus without thought, exists, it cannot learn. You cannot insert the knowledge you've acquired into a mind that doesn't exist.
When thinking first became something that could be done, the first thinking creature thought before learning anything. Without logic to base it on, thought can be rather random, but it is thought regardless of its nature.
'Learning without thought is labor lost; thought without learning is perilous.' (Analects 2.15) Both learning and thinking are essential processes. However, without learning something, there is no value in thinking. Say, for example, that you are thinking about ways to stop global warming. You might think up a myriad ways, but if you haven't based those solutions on what you've learnt, they're useless. That's why many people are under the illusion that locally-grown food is always superior to non-local food, when in fact, how the food was produced is a more important factor.
'I have been the whole day without eating, and the whole night without sleeping; occupied with thinking. It was of no use. The better plan is to learn.' (Analects 15.9)