Why was the multiplier so crucial to Keynes in The General Theory in terms of explaining how nations spend their way out of recessions? Explain carefully and completely. If R.F. Kahn had not invented the multiplier and Keynes had not used it, would The General Theory have had the same impact? Why or why not? Explain

Why was the multiplier so crucial to Keynes in The General Theory in terms of explaining how nations spend their way out of recessions? Explain carefully and completely. If R.F. Kahn had not invented the multiplier and Keynes had not used it, would The General Theory have had the same impact? Why or why not? Explain