It seems epistemically vicious to induce or maintain a belief for which one has insufficient evidence.
But suppose that my evidence supports a quite low degree of confidence about (a) whether I have or will have any higher-order beliefs, (b) the reliability of my introspection into higher-order beleifs, and (c) whether I am capable of self-inducing a belief. I now try to self-induce a belief that I have a higher-order belief, reasoning: either I’ll succeed or I’ll fail in self-induction. If I succeed, I will gain a true belief—for then I will have a higher-order belief. If I fail, no harm done. So I try, and I succeed.
Nothing epistemically vicious has been done, even though I self-induced a belief for which I had insufficient evidence.
In light of my evidenced low degree of confidence in the reliability of introspection into higher-order beliefs, once I have gained the belief, I still on balance have insufficient evidence for the belief. But it doesn’t seem irrational to try to maintain the belief, on the grounds that one can only successfully maintain it if one has it, and if one has it, it’s true. And so I try to maintain the belief, and I succeed. So I maintain the belief despite continuing insufficient evidence, and yet I am rational.
Here’s a reverse case. Let’s say that I find myself with very strong evidence that I will do not have and will never have any higher-order beliefs. It would be irrational to try to get myself to believe this proposition on this evidence.
So perhaps we should tie rationality not to evidence for a belief, but to evidence for the material conditional: if I have the belief, it is true?
Cf. this about assertion.