Several ways to call non-static method from static method: One way is to use

new

keyword followed by the class name

(new Foo)->nonStaticMethod();

Another method is to use

self

which comes after

new

keyword

(new self)->nonStaticMethod();

Complete example:

class Foo {

    public function nonStaticMethod()
    {
        return 'non-static';
    }

    public static function staticMethod()
    {
        // return (new Foo)->nonStaticMethod();
        return (new self)->nonStaticMethod();
    }
}

echo Foo::staticMethod();

The second method

new self

is better, because if we want to rename the class later, we will not need to change the class name more than one place