The thing that strikes you is how learning about Kierkegaard the man is vital to understanding his way of thinking (second only to learning how to spell his name of course). What is most interesting is that he doesn't think of philosophy as some kind of abstract ideas, but as integral to being human:
"Instead of excluding his personal life from his intellectual work, he turned his experiences of love, suffering, spiritual weakness, moral conflict and despair into philosophical problems, and insisted that these could not be addressed through rational, abstract thought. Kierkegaard argues that objectivity is dishonest and unable to capture what is most fundamental to human existence, because before anybody becomes a philosopher - and even, in fact, before they start to think about anything - they are already an 'existing individual' who lives, breathes and moves continually closer to death. The idea of an 'existing individual' is absolutely central to Kierkegaard's philosophy, but of course this is more than just an idea, and abstract concepts fail to capture the vitality and fluidity of life." (p.15)
There is much debate about the distinction between the person he was and the person he presents as in his writing; was he trying to create alternate personas for himself, or is it the case that it allowed him to posit all kinds of potentially unpopular views and arguments. The vast majority of his writings were published under a series of pseudonyms. He argued that the aim was to distance himself from the reader so he would not be viewed as some kind of authority figure. Heavily influenced by the thought of Socrates his aim was not to present a coherent package of ideas or 'truths' but to lead students to find the truth for themselves. He did not want to tell people how they should live, but encourage them to think for themselves.
"One of his priorities is to awaken readers to their capacity for choice, and by refusing the role of author and authority-figure he is giving the reader the opportunity to exercise her freedom." (p.38)
Kierkegaard's critique of Hegel, an important and influential german philosopher of the time, was an ongoing theme in much of his writing; his influence is significant if you consider how much time and effort Kierkegaard put into it (here talking about Either/Or).
"By dramatising the philosophical debates of his contemporaries, he takes the issues out of the purely reflective, theoretical context, and into actual existence. There is in Kierkegaard's thought an attempt to move beyond academic philosophy, as well as to criticise Hegelian ideas in particular. This means that his relationship to both philosophical traditions and the academic world is rather ambiguous: on the one hand he draws from concepts created by other philosophers, which were already topical - such as Aristotle's principle of contradiction - but on the other hand he uses these concepts to argue that philosophy cannot express the whole truth about human existence." (p.56)
He wanted to shift the focus of thinking away from Hegel's insistence on objective truth, for Kierkegaard the 'inwardness' of the individual was all important. As the book points out, "Kierkegaard's philosophy reflects a common experience of feeling occasionally at odds with the world and unable to express oneself fully within it", and perhaps this is why he has come to be linked so closely with 20th century existential philosophy. For him subjectivity was more significant:
"'Subjectivity is truth' means that truth is a way of being a subject, or a way of existing as a human being. Kierkegaard says that subjective truth is a matter of how - how one lives - whereas objective truth is a matter of what one knows or believes." (p.68)
"Right through Kierkegaard's authorship there runs the claim that, from an existential point of view, intellectual reflection alone is unable to reach the goals of ethical and religious life. Religious faith is presented as a greater task and a rarer achievement than rational thought." (p.61)
I begin to loose contact with him at this point because he moves off into the realm of theology and I skimmed though the last part of the book. In the same way that Descartes came up with all sorts of interesting challenges to mainstream thinking of the day, he baulks at actually questioning the existence of god. Challenging the doctrines of the church is one thing, anything that might undermine their essential message is quite another. There are some interesting introduction to critiques of Kierkegaard on his Wikipedia page if you are interested. So, a very interesting person, privileged by his independent wealth to spend his life thinking about what it means to be human, something that we should all do from time to time.
"He wrote a book on the topic, with a title that summed up his quandary: Either / Or. Either get married to Regine or don’t get married. What’s it best to do? Settle down to family life? Or look for someone else? Stay single? Or settle for what you know already? After a year of agony (of angst), he broke off the engagement. But he pined for Regine nevertheless, leading to a memorable outburst: 'Marry, and you will regret it; don’t marry, you will also regret it; marry or don’t marry, you will regret it either way. Laugh at the world’s foolishness, you will regret it; weep over it, you will regret that too… Hang yourself, you will regret it; do not hang yourself, and you will regret that too; hang yourself or don’t hang yourself, you’ll regret it either way; whether you hang yourself or do not hang yourself, you will regret both. This, gentlemen, is the essence of all philosophy.' "(Quoted from The Philosopher's Mail)