Tom Elliott posted a calendar plot of bus delay times on Twitter. My first reaction was, these little area graphs look like cats! Five seconds later, I saw Luis A. Apiolaza’s reply: They look like cats! All of a sudden, Murphy’s Law came to my mind, and I have got Yihui’s Cat-looking Law. For the record, the full text of the law is:
Anything that can look like cats in your eyes, will look like cats in some other people’s eyes.
P.S. Below are two of my favorite cats pictures.


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As a freelancer (currently working as a contractor) and a dad of three kids, I truly appreciate your donation to support my writing and open-source software development! Your contribution helps me cope with financial uncertainty better, so I can spend more time on producing high-quality content and software. You can make a donation through methods below.
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Venmo:
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If you have a Paypal account, you can follow the link https://paypal.me/YihuiXie or find me on Paypal via my email
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Please feel free to email me if you prefer a different way to give. Thank you very much!
I’ll give back a significant portion of the donations to the open-source community and charities. For the record, I received about $30,000 in total (before tax) in 2024-25, and gave back about $15,000 (after tax).