关于php承袭的疑惑

关于php继承的疑惑

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?phpclass A {    [color=#FF0000]private[/color] $name = "Nciaer";    public function say() {        echo $this -> name . "<br>";    }}class B extends A {    public $name = "Fansa";}$b = new B();$b -> say();?>

输出结果：
Nciaer
----------------------------

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?phpclass A {    [color=#FF0000]public[/color] $name = "Nciaer";    public function say() {        echo $this -> name . "<br>";    }}class B extends A {    public $name = "Fansa";}$b = new B();$b -> say();?>

输出结果：
Fansa


为什么父类变量$name为public的时候，$b调用成员方法say()输出子类的$name;
当父类变量$name为private时，$b调用成员方法say()输出父类的$name;

------解决方案--------------------
private 私有的
怎么能被继承呢？