Clearly, Perl is a unique language. This uniqueness has brought forth a community and an ideology that is unprecedented with other languages. One does not have to be a member of this community or agree with this ideology to use Perl, but it helps to at least understand the ideology to get the most out of Perl.
The common Perl slogans have become somewhat famous. These slogans make up the "Perl ethic"--the concepts that guide the way Perl itself is built, and the way most Perl programs are written.
"There's more than one way to do it". This slogan, often abbreviated TMTOWTDI (pronounced TIM-toady), is common among many programmers, but Perl takes this idea to its logical conclusion. Perl is rich with non-orthogonality and shortcuts. Most major syntactic constructs in Perl have two or three exact equivalents. This can be confusing to newcomers, but if you try to embrace this diversity rather than be frustrated by it, having "more than one way to do it" can be fun.
"The Swiss Army chain-saw". This is the somewhat "less friendly" summary of the previous term. Sometimes, all these diverse, powerful features of Perl make it appear that there are too many tools that are too powerful to be useful all together on one "Swiss Army knife". However, eventually, most Perl users find all these different "chain-saw"-style tools on one "Swiss Army" knife are a help rather than a hindrance.
"Perl makes easy jobs easy, and the hard jobs possible." This is a newer phrase in the Perl community, although it was originated by Alan Kay decades ago, but it is quite valid. Most easy tasks are very straightforward in Perl. As the saying goes, most programmers find that there are very few jobs that Perl cannot handle well. However, despite what the saying might indicate, Perl is not a panacea; the programmer should always choose the right tool for the job, and that right tool may not always be Perl.
"Perl promotes laziness, impatience and hubris." These seem like strange qualities to be promoting, but upon further analysis, it becomes clear why they are important.
Lazy programmers do not like to write the same code more than once. Thus, a lazy programmer is much more likely to write code to be reusable and as applicable in as many situations as possible.
Laziness fits well with impatience. Impatient programmers do not like to do things that they know very well the computer could do for them. Thus, impatient programmers (who are also lazy) will write programs to do things that they do not want to have to do themselves. This makes these programs more usable for more tasks.
Finally, laziness and impatience are insufficient without hubris. If programmers have hubris, they are much less likely to write unreadable code. A good bit of hubris is useful--it makes programmers want to write code that they can show off to friends. Thus, hubris, when practiced in the conjunction with laziness and impatience, causes programmers to write reusable, complete and readable code. In other words, it is possible to exploit these three "bad" traits to obtain a "good" outcome.