Donald hebb response which contributea more to the area of a rectangle its lenght or it width?

There isn't an answer to the question, and that's the point. Hebb was suggesting that trying to ascribe variation in humans to this much genetics and this much environment is as misguided as trying to ascribe variation in the area of a rectangle to this much length or this much width: it can't be done, because one is as essential as the other and they fundamentally inter-relate.