Ap Dijksterhuis

On which day was the lake half covered with water lilies?

Now, if you hear such a riddle, your conscious mind is inclined to just say, okay, so you start with one lily and then the next day there's two and then the third day there's four.

But this is not going to get you anywhere.

And what you need is insight.

You need this sudden flash where you understand the riddle.

And this is usually...

This usually occurs to you only when you take a little distance first and maybe even, you know, go and take a walk or something.

And then you realize, well, okay, if after 60 days the lake is fully covered and the number of leaves doubles every day, then of course half covered means it's the day before the last day.

It's on day 59.

And if the right answer comes to you,

It comes in a sort of a flash.

It never comes when you approach it very analytically or consciously.

Yeah.

And then understanding the problem by turning it on its head is already the solution.

Because then once you know it, you know it's actually incredibly simple.

Yeah.

Yeah.

I think it started about 30 years ago where scientists discovered that during sleep we engage in memory consolidation.

So this means actually if you learn something then during REM sleep we consolidate this information so that the next day we have better memory.

And then people started to do more and more experiments and also more complex experiments where in the evening