Title text: At least, with p<0.05 confidence.
This comic was published 2 months after Randall's then fiancée, now wife, was diagnosed with breast cancer (see Category:Cancer), which is likely what inspired this comic - even though Cueball sounds like he is the one afflicted by the sickness. The comic is thus about the existential questions that might arise from such a crisis. The moral could be interpreted as that you shouldn't begrudge your fellow human being, regardless of where they find comfort.
Also, any sentence is instantly funny if, at the end of it, you address your audience as "bitches". It may also be a reference to 54: Science.
"Slings and arrows of fortune" is an allusion to the "To be, or not to be" soliloquy in William Shakespeare's Hamlet, Prince of Denmark. Hamlet asks himself whether it is "Nobler in the mind to suffer / The Slings and Arrows of outrageous Fortune" (to resign oneself to one's fate and endure what may come), or to "take Arms against a Sea of troubles, / and by opposing end them" (to commit suicide and end suffering); he ultimately concludes that we would rather face the dangers and pains we know on Earth than whatever unknown new ones may come in the afterlife. Cueball appears to agree with Hamlet, thanking "the people who refused to gracefully accept the ineffability of reality": Religion and spirituality can give him the moral courage to face his death, but he'd much prefer to not die in the first place, and won't have to, thanks to medical and scientific innovation.
The title text is a pun based on Cueball's newfound confidence, asserting that his statement "because they work, bitches" has a 95% confidence interval.
- [The three panels are arranged diagonally, upper left to bottom right.]
- [Two people are walking past a tree. One is White Hat.]
- White Hat: So, has this sickness opened you up to looking for answers beyond science?
- Cueball: ...no, not really.
- [Cueball turns to face White Hat.]
- Cueball: We've groped for comfort before the slings and arrows of fortune for millennia, and I begrudge nobody their sources of solace.
- Cueball: But Science provides tools.
- Cueball: $100 billion a year in scientific studies and medical R&D has bought us some pretty damn powerful slings and arrows of our own.
- Cueball: This world is amazing, and I'm going to live to experience more of it thanks to people who refused to gracefully accept the ineffability of reality.
- Cueball: I find my courage where I can, but I take my weapons from science.
- Cueball: Because they work, bitches.