"Ye see yon birkie, ca'd a lord,
Wha struts, an' stares, an' a' that.
"Oh yes, I do love that bit," she chuckles, her laugh deep, long and very merry.
She is talking to me from her home in Winston-Salem, North Carolina, on the eve of her 80th birthday, and she assures me she still has plenty to laugh about. "My bones will not let me forget my age, but my spirit is young," she says. "I'm really just a teenager at heart. I have everything to be thankful for."
Born Marguerite Johnson in St Louis, Missouri, 80 years ago today on 4 April 1928, Angelou has had a colourful and at times arduous life, which has been depicted in detail in six volumes of memoirs. Most famous is the first book, I Know Why The Caged Bird Sings: published in 1969, this frank and moving account of her childhood catapulted her to literary stardom. Raised by her grandmother in Stamps, Arkansas, she was raped by her mother's boyfriend at the age of seven, after which the young girl did not speak a word for nearly six years, rendered mute by this appalling trauma.
It was as a child that she discovered Burns, along with countless other poets and writers, and eventually – thanks to an inspirational schoolteacher who insisted that to truly enjoy poetry, one must read it aloud – began to talk again.
"When I was a little girl in Arkansas, I began to read Burns and I couldn't figure out the language he was using," she says. "I've always loved puzzles, though, and I got a dictionary. I did my best, and eventually I did work out what he was saying and I loved it. His spirit was a humanitarian spirit, he was able to love human beings, and his imagination was vast."
By 17, she was a single mother. While she raised her young son, Guy, she earned money to keep them both by dancing at a strip joint and running a brothel. In her early twenties she married a Greek sailor named Tosh Angelos, but was divorced within two years (she has married again more than once, but refuses to dwell on the number of times). She has worked as a cook and a streetcar (tram] conductor, worked in a mechanic's workshop stripping paint from cars, as an editor for an English-language newspaper in Egypt, been an Emmy-nominated actress, a producer, a playwright and a director, and has been nominated for the Pulitzer Prize. She is also, of course, a renowned and seemingly tireless civil rights activist.
Now entering her ninth decade Angelou remains stubborn in her refusal to retire, writing from home, teaching American studies at Wake Forest University and travelling the country in her role as a speaker. She is a great-grandmother, speaks several languages and has published numerous volumes of poems and children's stories.
Her achievements and accolades are too extensive to list in full here, but she insists that there is still more she wishes to do. "I need to be a better human being," she says. "Kinder, truer, more patient, more supportive, analytical but not critical. I'm trying to be a Christian, but it's not something you achieve (then] sit back and rub your hands together gleefully and say, 'I've got it.'"
Asked about the hardships she has faced and whether there is anything about her astonishing life she would choose to change, Angelou responds by singing an old African-American gospel song to me, her voice low, husky and sweet;
"Now Lord don't move my mountain,
But give me the strength to climb,
And Lord, don't take away my stumbling blocks,
But lead me all around."
"That's the way I see it. There are things I wish I had known better," she explains. "I wouldn't have done certain things maybe, but who I'm trying to be today and even where I've arrived so far, I'm grateful for it. I've come through some harrowing times and some very painful times, but I've come through."
Tomorrow she will celebrate her birthday with a party in Florida, thrown by her close friend the talk-show host Oprah Winfrey. "It's going to be a surprise, but I love surprises," she says. "We all have that child in us, the one who wants to be a little afraid, but delighted. That's what a surprise is. You look forward to it with just a little trepidation." The day will have particularly poignancy for her, however, it also being the 40th anniversary of the death of her great friend Dr Martin Luther King Jr. For years after his assassination, she refused to celebrate her birthday, preferring instead to take the time to remember Dr King with his wife, Coretta. Until Coretta's death in 2006, each year on Angelou's birthday the two friends would talk on the telephone and send each other flowers.
"He, his dreams and my country will be in my thoughts tomorrow. And so will Coretta," she says. Were Dr King alive today, how does she think he might reflect on the progress made in terms of civil rights?
"I don't think he was impatient. I think he knew he had to do what he had to do while he was here," she says. "But you see, the idea of freedom, the thought of liberation, the concept of justice is so vast that I don't believe he thought it could have been achieved in ten years, or in 40 for that matter.
"I think he would hope that there would be some people carrying on and that we would be becoming better and better, and I think we are. Not as fast as we'd like to, not as fast as we need to, not as comprehensively as we must, but we are becoming better. The two front-runners to become president of this United States in the Democratic party are a white woman and a black man. You know that we've come a long way for each of them to be seriously considered."
Angelou has chosen to publicly voice her support for Hillary Clinton, a fact that she has joked about with Winfrey, who has chosen to back Barack Obama. She wasn't torn between supporting a woman and supporting a black man, she says, but rather has admired Clinton for years.
"While I respect Senator Obama, I've been watching Hillary Clinton for over 20 years, since she was the wife of the Governor of Arkansas," she says. "I saw how she carried herself. I said to myself then that if she ever runs for anything, I'm going to support her. I think Hillary Clinton would be the best president we could possibly have."
Angelou speaks with as much measured passion on the topic as when she recites Burns, discusses her students, laments human rights failures ("we have so many brutalities on this planet that, if you had a globe, you could spin it around and put your finger anywhere, whether it's Tibet or Londonderry, and we just have so many civil rights denied") or simply cracks a joke, attempting a broad Glaswegian accent with a rendition of I Belong to Glasgow, pronouncing the Scottish city "Glas-gee" before erupting with laughter.
However, she insists that, despite her experiences and observations, she believes she still has much to learn and that at 80, life still presents very few answers. "I believe we sit around and preen and pretend to know something, but to tell you the truth I think we know very little," she says.
"We take on some answers and wear them and disclaim them and orate and carry on and let our voices rise and fall on some superficial wisdom. Or maybe, we know that love heals, but some people pretend they don't even know that. But the older I become, the less I know. I'll think I have an answer and then it flitters away on the morning breeze."