Here is a contradictory pair of investing proverbs:

a) Cut your losses and let your profits run.

b) Buy low, sell high.

(Obviously, when you cut your losses you are selling low, and when you let your profits run you are not selling high).

Here's another:

a) Don't try to catch a falling knife.

b) Buy when there's blood in the streets.

None of these proverbs actually gives you reliable, actionable information. All they really do is provide confirmation bias--whatever you decide to do, a proverb that supports it pops into your mind and gives you false confidence, whatever your decision was.

One proverb that sounds illogical at first is „You can’t have your cake and eat it“ (<a href="https://en.m.wikipedia.org/wiki/You_can%27t_have_your_cake_and_eat_it">https://en.m.wikipedia.org/wiki/You_can%27t_have_your_cake_and_eat_it</a>;)

I understand the meaning but it’s confusing and I’d rather use „you can’t have it both ways“.

 I also think that „sleeping like a baby“ is nonsense. Millions of sleepless parents know what I’m talking about.

Oh, @Dan! You have hit the nail on the head. There is a proverb for everything, reasons for everything and currants for the cake!

@Ksenia. They certainly are not. Yes, the same dubious expression exists in English. Perhaps a Napoleonic agent had insinuated it into both languages in a plot to undermine us both?

It's not a proverb really but I've always had mixed feelings about the expression "спать как младенец" ("to sleep like a baby"). I mean, I'm not an expert but to me it seems like babies are not really the best sleepers in the world. Or are they?