A physical ailment can cause you to suffer. Exposure to things that can water the seeds of fear and hate that we all posses can cause you to suffer. In order to achieve nirvana, you must identify and eliminate all suffering. Nirvana is, in fact, the elimination of not only all suffering but also all concepts, all thought. In The Phantom Menace , when Anakin faces the Jedi Council, Yoda questions him about his mother.
Fear is the path to the dark side.
What Yoda was telling him is that being controlled by fear makes it impossible to eliminate suffering and find happiness. As we already know, Anakin ultimately will allow his fear to get the best of him and lead him to the dark side. A Jedi is not a Buddha. These are not principles or teachings of Buddhism. It is not the aim of this article to convince you that the Jedi are space Buddhists.