Belief and Love both ask for Trust instead of Tests! Those looking for verification of belief and love often, unfortunately, end up in failure.
Scientific investigation, logical analysis, and a purely reason based discourse are less likely to give conclusive supportive evidence for either and we are often left with only our trust in someone in both cases.
Science works on the basis of testing a hypothesis and either accepting or rejecting it on the basis of findings after taking care of all known variables. Science, thus, breeds on doubt and grows on proofs as a result of continuous testing. Belief and Love on the other hand breed on Trust and vanish when doubts start arising requiring tests for proofs!