Knowledge and imagination is hands on hands in any work. Without imagination knowledge has know value, similarly without knowledge imagination has no value. People generally imagine based on his knowledge. Almost all innovation has happen with imagination, but behind that imagination there was a handful of knowledge. In the above suggested line, I do not completely agree with the author with following reasons.
First, without knowledge the imagination is difficult. In college and university, first professor teach the student about the subject, further student try to realize those knowledge and imagine more about the subject. On the basis of their imagination, they do academic projects on the instruction of college professor. So, first people learn about the things and then they use it in real life after that they go for new imagination. Basically, imagination is nothing but inspiration of work, for instance a thief will almost every time imagine about his skill of stealing. He will think that how to improve his skill, how to do better stealing in the specified location. Basically, he has basic knowledge of stealing and then he will think about better stealing skill.
Similarly, suppose a people had imagine that they will made a machine which will follow the human instruction. Then, they will think that how to embed the instruction in machine so that it could sense itself and start follow it according to situation. Now, they need skill to do programming those instruction, but if they do not know about programming then their imagination will not be able to complete. People generally imagine according to their circumstances for example Thomas Alpha E has imagine about the electric bulb, but behind his imagination, he has knowledge of electricity. He had clear knowledge that electricity is going to supply power by which a bulb will illuminate. So, knowledge always force person to imagine above their strength.
However, without the imagination knowledge has less value. In college,when professor taught about a topic suppose Moment of Inertia effect while a passenger is moving in car, then he expect student to imagine it properly because moment of inertial can be feel instead of learning. In the other hand, If student has learn about the subject, but he does not have clear imagination then he wont be able realize the subject properly. Whenever he will face new problem on the same concept then he wont be able to solve it with full confidence. So, knowledge and imagination are inseparable for any work. If some scientist, with knowledge, would not have imagine about telephone then it would not have been possible to connect with our friends who is living thousand of mile away.
In the aforementioned reasons in the paragraph. imagination need a initial knowledge. Without knowledge imagination could not be more effective. In the paragraph one and two, it is elucidated that behind any imagination, knowledge has to play sufficient role. In third paragraph, it is clear that knowledge and imagination are required for any innovations.