Raymond Smullyan doesn’t believe in astrology.
When asked why, he says, “I’m a Gemini.”
Science & Math
A Cosmic Coincidence
Light travels 186,000 miles per second. The average diameter of Earth’s orbit is 186 million miles.
So, on average, sunlight reaches us in a neat 500 seconds.
Digit Acrobatics
Quine’s Paradox
“Yields a falsehood when preceded by its quotation” yields a falsehood when preceded by its quotation.
Easy as Pie
Now I will a rhyme construct,
By chosen words the young instruct.
Cunningly devised endeavour,
Con it and remember ever.
Widths in circle here you see,
Sketched out in strange obscurity.
Count the letters in each word.
One Solution
The Professor brightened up again. ‘The Emperor started the thing,’ he said. ‘He wanted to make everybody in Outland twice as rich as he was before — just to make the new Government popular. Only there wasn’t nearly enough money in the Treasury to do it. So I suggested that he might do it by doubling the value of every coin and bank-note in Outland. It’s the simplest thing possible. I wonder nobody ever thought of it before! And you never saw such universal joy. The shops are full from morning to night. Everybody’s buying everything!’
— Lewis Carroll, Sylvie and Bruno
Couch Logic
Your vote will make a difference only if it breaks a tie or creates one.
This is very unlikely to be the case.
So why vote?
Math Notes
99 + 19 + 29 + 99 + 89 + 59 + 19 + 59 + 39 = 912985153
The Mpemba Effect
When University College physicist Denis Osborne visited Mkwawa Secondary School in Iringa, Tanzania, in 1963, he little expected the question he got from student Erasto Mpemba:
“If you take two similar containers with equal volumes of water, one at 35°C and the other at 100°C, and put them into a freezer, the one that started at 100°C freezes first. Why?”
The other students derided Mpemba, but he was right — in cooking class he’d noticed that hot ice cream mixes froze more quickly than cold ones.
Osborne confirmed the effect and shared a publication with Mpemba in 1969. What’s behind “the Mpemba effect” is still something of a mystery — it seems to be a combined result of supercooling, convection, evaporation, and the insulating effect of frost. (If you want to conduct your own experiment, start with containers at 35°C and 5°C.)
Proof That -1 Is Positive
Let
Clearly S is positive. Now multiply each side by 2:
But that’s just the same as S minus 1.
And if 2S = S – 1, then S = -1.
So -1 is positive.