Anthropic Principle:

The Universe is as it is because we exist.

Brandon Carter (1974) coined the phrase Anthropic Principle with the definition

What we can expect to observe must be restricted by the conditions necessary for our presence as observers.

We may thus not only occupy a preferred place and/or preferred time, we may also occupy a preferred universe. This uncomfortable idea may follow from several vexing facts about our Universe:

It does appear as though we live in a special universe. Some quantities assume highly improbable values, for example, the flatness of the Universe is disturbing. Several questions are: These questions are interesting in the sense that if we can understand the origins of the above problems, this would imply that we understand how the Universe was constructed (in the beginning) which would be intellectually satisfying and would also offer, the admittedly rather far-fetched notion, that we could engineer the space-time structure of the Universe.

Note that if some of the finely-balanced quantities were not finely-tuned then our Universe would have grossly different properties. The properties would, in fact, be so different that it is highly likely that life (as we know it) would not develop and we would not be around to ask the question of why does the Universe appear special. That is, selection effects would say that it is only in universes where the conditions are right for life (thus pre-selecting certain universe) is it possible for the questions of specialness to be posed.

This statement and variants of this statement are the gist of the Anthropic Principle. Note that the Anthropic Principle is probably true and says that there is nothing mysterious about why our Universe is special. However, it does not rule out the possibility that there is a deeper level to our understanding of the Universe which makes our Universe the most probable universe from the plethora of all possible universes. This still may be true but is not required philosophically or scientifically.