Proof is a dangerous word in the context of science because its common, scientific, mathematical and legal meanings are all different. This has been used to discredit scientists when they are asked, for example, to ‘prove’ evolutionary theory, that genetically modified foods can do no harm or that something else is irrefutably true. Such demands are at odds with the nature and process of science, which can disprove things that are untrue but be unable (philosophically) to prove them. Science is said to support propositions with varying degrees of probability (see significant, statistically significant), which may be so consistently high that the propositions can be relied on. Safer alternatives to proof that are often used include supported, established and demonstrated:

Despite the above, proof and prove have technical meanings within science and technology – for example, ‘proving’ cannons to show that they are functional and the ‘proof’ of spirits of a certain strength.

proof (mathematics): a statement shown to be valid by logical argument

proof (legal): that which has been declared to be so by a jury, judge or legal authority