事實上有不少社會學家認為，馬蹄鐵理論是不可信的。而瑞德大學 (University of Reading)學者巴克(Peter Barker)在自己所著的書《民主德國和其歷史 (GDR and Its History)》中，引述谢菲尔德大學湯遜 (Peter Thompson)的批評，認為馬蹄鐵理論扭曲了左右派政治主張不同的距離，更不滿意這個理論無法打破傳統的政治學直線軸，相類似主張之間連貫性。.
- A Friendship. 《費加洛報》. 2004 [2009-02-13].
Jean-Pierre Faye's famous horseshoe theory (according to which extremes meet) finds verification here more than in other places, and the two states of delirium often mingle and meet, unfortunately spreading beyond these extremist circles. But contrary to the legend deliberately maintained and/or the commonplace believed in good faith, Israel and the United States have not always been allies; on several occasions their relations have even been strained.
- The Political Horseshoe again. AIJAC. [2009-02-13].
I think Mr. Loewenstein has done a good job demonstrating why many people believe, as the “political horseshoe” theory states, that there is a lot more common ground between the far left, where Loewenstein dwells politically, and the far right views of someone like Betty Luks than people on the left would care to admit.
- Josef Joffe. New Year’s Essay 2009 - For Roland Berger. Roland Berger. 2008-12-22 [2009-04-19].
- Political Science Terms. Political Science Scholar. [2009-04-19].
- Political Research Associates: Study the U.S. Political Right
- University of Reading: Peter Barker
- University of Sheffield: Peter Thompson
- GDR and Its History pp103