This morning, a friend sent me a text, saying: "It's going to be an ugly day. I only got four hours of sleep last night." I empathized with them, replying: "Sorry to hear that."

But then I remembered a blog post that I had written last year about starting one's day by declaring, "It's going to be a great day." In fact, I had used that very expression just minutes before receiving my friend's text. I found the link to the post—A great day—and sent it to them with the message, "This might help."

My post referenced the research of behaviour scientist BJ Hogg, who recommends this tiny habit: "In the morning, when you wake up and put your feet on the floor, say out loud: 'It's going to be a great day.'" And if that doesn't feel quite right, try one of Hogg's variations: "It's going to be an amazing day." "It's going to be an awesome day." "Today is going to bring good things." And on days like the one my friend was embarking on: "It's going to be a great day ... somehow."

Less than five minutes after I sent the link to my friend, they replied: "Today is going to be great. I'm going to rebel against negativity."

This evening, I received another text from my friend: "Definitely not my best day... but not a bad one, either." They concluded their message with this: "Going to reset and rearm for tomorrow."

The exchange reminded me of The Poetry Pharmacy, which publisher William Sieghart created when he began giving individuals a poem as a prescription for their worries. For example, his prescription for loneliness was a 700-year-old poem by a Persian poet named Hafez: "I wish I could show you, when you're lonely or in darkness, the astonishing light of your own being." Like Sieghart, I often share prescriptions for what ails a friend, though in my case the prescription is in the form of a blog post rather than a poem.

The correspondence with my friend also reminded me of Lin-Manuel Miranda's Gmorning, Gnight!, which a dear friend sent to me a few months into my cancer journey. Miranda's book presents a series of paired messages: one in the morning and another in the evening. An example:

I will leave these prescriptions for my friend, along with the assurance that every day is a new day to bring good things to life.