If a person should have broad knowledge of many academic subjects or specialize in one specific subject, it has been a hot topic being debated. We are living in an age with knowledge explosion and more and more society work have been divided into a number of fine pieces. A person is supposed to focus on the small part of his task and be proficient in the specific field. Thus the more concentrated a person is, the better his work will be done. However, many cross-discipline subjects spring up in recent years and the one specific subject you focus on is probably supported by many knowledge of other subjects. So a broad knowledge will benefit the whole work you are doing. Both aspects are equally important and the direction you choose depends on your demands and which stage your career or education are in.
With rapid development of technology, many fields require a high degree of precision. So if you focus on some specific subject, you will become more professional and make yourself more reliable. For example, if you are studying to be a doctor, it will be a better choice to choose certain areas of specialization than to be a general practitioner. From an economical perspective, you will probably make more money because the patients trust the specialists in just one of branches in medical science.
However, except for the specific area you want to develop our career, to gain more knowledge as possible as we can is also important. Think some knowledge gurus in old times like Da Vinci, he possessed outstanding insight in multiple fields across philosophy, mathematics and arts. The more knowledge a person have, the wider his vision will be. Many subjects also have inner connection so that you can understand the world better if you master more.
To put it more generally, specialization in one particular field is the main current of the age- we should all consider picking a specific major and be devoted to it. But foundational knowledge of all basic subjects is a prerequisite for specific expertise, while cross-discipline understanding and insight further one's advancement in certain domains. We might conclude on the note of having specialization as a spearhead driven by a thick and broad trunk of background knowledge.