supposition
noun [ C or U ] uk/ˌsʌp.əˈzɪʃ.ən/ us/ˌsʌp.əˈzɪʃ.ən/
猜测，推测，假定
the fact of believing something is true without any proof or something that you believe to be true without any proof
That article was based on pure supposition. 那篇文章纯粹是基于推测。