If it is this hard to guess accurately about a single industry, then what about the overall direction of the economy? It is far more complex, far more chaotic; like a kaleidoscope, it changes completely when any outside force is brought to bear on it; and there are countless outside forces which might intrude.
單一產業都說不准，何況整個經濟要素盤根錯節，瑣細而零亂，正如一隻超大型萬花筒，任何一點外力振動下，整個圖像就要全盤改寫，更別提外力從四面八方湧進，又朝千百個不同的方向拖曳。