Now consider another case: a coin of unknown bias is to be tossed. That is, you have not seen any data on previous tosses. In the absence of any relevant information about the bias, symmetry concerns might suggest you take the chance of heads to be around a half. This opinion is different from the above one. There is no weight of evidence, but there is nothing to suggest that your attitudes to \(H\) and \(T\) should be different. So, on balance, you should have the same belief in both.