This may be the only place you can find the English translation of the Barron von Münchhausen bootstrapping story anywhere (see below), which is a little odd because the Münchhausen Trilemma is such an important philosophical issue.
For a more complete understanding of the concept, I invite you to click on the link and read, but for my purposes The MünchhausenTrilemma demonstrates that rationality (i.e. thinking) must have input from some source other than itself. Rationality is like a calculator in that it requires a finger from somewhere to press the buttons.
The input comes from consciousness. Rationality is but a tiny subset of our larger consciousness. Feelings bubble up into ideas (rationality) and those ideas become words for the very limited purposes of communication and the creation of labor-saving devices. Those feelings come from our connectedness to all that is, not from our own thinking.
That's why a so-called "rational" approach to life (as opposed to a consciousness-based approach to life) is considered bootstrapping. It does not allow for this input from all that is. It simply assumes that the thinking started up on its own. That the calculator pressed its own buttons.
[As always, you need not take my word for any of this. Go into your body and make your own determination as to the nature of reality.]
The world of Science (what I would call the Religion of Science) would have you ignore this point. As stated aptly on Rationalwiki.org:
The Münchhausen Trilemma is a problem in philosophy that all statements can be questioned and then need evidence. This problem has been well known in philosophy for thousands of years, but rarely gets addressed because it breaks the legs of philosophy, science, and any other possible approach to reality.
The story behind the below quotation is interesting.