Hitchens’ razor is an epistemological rule of thumb which asserts that any person who makes a claim about ‘the way the world is’ takes on the burden of proof for proving it is so.
The razor is usually formulated as follows:
What can be asserted without evidence can be dismissed without evidence.
It is a translation of the Latin proverb Quod gratis asseritur, gratis negatur (What is freely asserted is freely deserted). Near the end of the 20th century, the razor was revived and popularised by the British-Amercian journalist and author Christopher Hitchens, hence its modern name.